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Wood-frame construction and sheet steel studs (9.23 and 9.24)

All of 9.23 and 9.24 with the span tables named in the guide (9.23.4.2.-A to -L, 9.23.4.3 to 9.23.10.7, lintel tables 9.23.12.3).

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Values this chapter turns on

max spacing of sill plate anchor bolts
2.4 m
max spacing of sill plate anchor bolts
minimum anchor bolt diameter for sill plates
12.7 mm
minimum anchor bolt diameter for sill plates
minimum end bearing for wood beams
89 mm
minimum end bearing for wood beams
max hole size in floor, roof or ceiling framing
1/4 depth
max hole size in floor, roof or ceiling framing

Section 9.23 is the biggest single source of Part 9 structural questions. Most answers are a value from a span table or a fraction from the notching rules. The span tables reward a disciplined reading order. Most wrong answers come from reading the right row in the wrong part of a table.

How to read a span table

Every span table in 9.23.4.2 works the same way. Go through these steps in order:

  1. Pick the table for the member: floor joists (A, B), ceiling joists (C), roof joists (D, E), rafters (F, G), built-up and glulam beams (H to K), or ridge beams and lintels (L) OBC Div. B 9.23.4.2.OBC Div. B 9.23.4.2. Spans for Joists, Rafters and Beams(1) Except as required in Sentence (2) and Article 9.23.14.10., spans for wood joists and rafters shall conform to the spans shown in Span Tables 9.23.4.2.-A to 9.23.4.2-G for the uniform live loads shown in the Tables. (See Article 9.4.2.2.) (2) Spans for floor joists that are not selected from Span Tables….
  2. Pick the part of the table. Floor joist Table A has three parts: strapping only, bridging only, and strapping plus bridging. Rafter Table F has parts for specified snow loads of 1.0, 1.5 and 2.0 kPa.
  3. Pick the row by species group, grade and size.
  4. Pick the column by spacing: 300, 400 or 600 mm.

The floor span tables only apply to residential floors, or to floors with no more than the residential live load. An office floor at 2.4 kPa must be designed under Subsection 4.1.3 OBC Div. B 9.23.4.1.OBC Div. B 9.23.4.1. Application(1) Spans provided in this Subsection for joists, beams and lintels supporting floors shall apply only where (a) the floors serve residential areas as described in Table 4.1.5.3., or (b) the uniformly distributed live load on the floors does not exceed that specified for residential areas as described in Table….

Size at 600 mm o.c. 2.0 kPa part 1.5 kPa part
38 x 140 3.08 m 3.40 m
38 x 184 3.89 m 4.41 m

The answer is 38 x 184. Choosing 38 x 140 means you rounded the snow load down to 1.5 kPa, which is the trap.

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Notching and drilling (9.23.5)

These rules turn into quick arithmetic:

Member Rule 38 x 235 joist or 38 x 140 stud
Hole in a floor, roof or ceiling member no larger than 1/4 of the depth, at least 50 mm from the edges hole up to 58 mm
Notch in a floor, roof or ceiling member on top only, within half the depth of the bearing, no deeper than 1/3 of the depth notch up to 78 mm deep, within 117 mm of bearing
Loadbearing stud at least 2/3 of the depth must stay undamaged at least 93 mm left, so remove at most 46 mm
Non-loadbearing stud at least 40 mm must stay undamaged
Top plate at least 50 mm of width must stay undamaged
Roof truss no notching or drilling unless the truss design allows it

Sources: OBC Div. B 9.23.5.1.OBC Div. B 9.23.5.1. Holes Drilled in Framing Members(1) Holes drilled in roof, floor or ceiling framing members shall be not larger than one-quarter the depth of the member and shall be located not less than 50 mm from the edges, unless the depth of the member is increased by the size of the hole., 9.23.5.2.OBC Div. B 9.23.5.2. Notching of Framing Members(1) Floor, roof and ceiling framing members are permitted to be notched provided the notch is located on the top of the member within half the joist depth from the edge of bearing and is not deeper than one-third the joist depth, unless the depth of the member is increased by the size of the notch., 9.23.5.3.OBC Div. B 9.23.5.3. Wall Studs(1) Wall studs shall not be notched, drilled or otherwise damaged so that the undamaged portion of the stud is less than two-thirds the depth of the stud if the stud is loadbearing or 40 mm if the stud is non-loadbearing, unless the weakened studs are suitably reinforced., 9.23.5.4.OBC Div. B 9.23.5.4. Top Plates(1) Top plates in walls shall not be notched, drilled or otherwise weakened to reduce the undamaged width to less than 50 mm unless the weakened plates are suitably reinforced., 9.23.5.5.OBC Div. B 9.23.5.5. Roof Trusses(1) Roof truss members shall not be notched, drilled or otherwise weakened unless such notching or drilling is allowed for in the design of the truss.. A larger hole or notch is allowed in a joist only if its depth is increased by the size of the hole or notch.

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Fasteners and anchorage (9.23.3, 9.23.6)

Nailing of framing follows Table 9.23.3.4.OBC Div. B 9.23.3.4. Nailing of Framing(1) Except as provided in Sentence (2), nailing of framing shall conform to Table 9.23.3.4. (2) Where the bottom wall plate or sole plate of an exterior wall is not nailed to joists or blocking in conformance with Table 9.23.3.4., the exterior wall is permitted to be fastened to the floor framing by (a) having…. The usual anchorage of a building frame takes one of two forms OBC Div. B 9.23.6.1.OBC Div. B 9.23.6.1. Anchorage of Building Frames(1) Except as required by Sentence 9.23.6.3.(1), building frames shall be anchored to the foundation unless a structural analysis that considers wind and earthquake loads and lateral earth pressures shows that anchorage is not required (2) Except as provided in Sentences (3) to (6), anchorage shall be provided by (a)…:

  • the first-floor joists are embedded in concrete; or
  • the sill plate is fastened with anchor bolts of at least 12.7 mm diameter at no more than 2.4 m o.c., embedded at least 100 mm, with nuts and washers.

Higher hazard changes this:

  • 2 or more floors on frame walls, with S_a(0.2) up to 0.70 or HWP of 0.80 to 1.20 kPa: at least two bolts per braced wall panel, either 15.9 mm at 2.4 m or 12.7 mm at 1.7 m.
  • S_a(0.2) over 1.8, or HWP of 1.2 kPa or more: anchorage is designed to Part 4.

Exterior posts are anchored against uplift and lateral movement. Low, small decks that are not attached to another structure are exempt OBC Div. B 9.23.6.2.OBC Div. B 9.23.6.2. Anchorage of Columns and Posts(1) Except as provided in Sentences (2) and (3), exterior columns and posts shall be anchored to resist uplift and lateral movement. (2) Except as provided in Sentence (3), where columns or posts support balconies, decks, verandas and other exterior platforms, and the distance from finished ground to the underside of….

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Beams, joists, studs and lintels

Beams and joists:

  • Beams need 89 mm of end bearing OBC Div. B 9.23.8.1.OBC Div. B 9.23.8.1. Bearing for Beams(1) Beams shall have even and level bearing and the bearing at end supports shall be not less than 89 mm long, except as stated in the notes to Span Tables 9.23.4.2.-H to 9.23.4.2.-K. .. Joists and rafters need 38 mm OBC Div. B 9.23.9.1.OBC Div. B 9.23.9.1. End Bearing for Joists(1) Except when supported on ribbon boards, floor joists shall have not less than 38 mm length of end bearing. (2) Ribbon boards referred to in Sentence (1) shall be not less than 19 mm by 89 mm lumber let into the studs..
  • Built-up beam members are 38 mm or thicker and on edge. Butt joints go over supports, or near the end quarter points of continuous beams. Nail in a double row of 89 mm nails at no more than 450 mm OBC Div. B 9.23.8.3.OBC Div. B 9.23.8.3. Built-up Wood Beams(1) Where a beam is made up of individual pieces of lumber that are nailed together, the individual members shall be 38 mm or greater in thickness and installed on edge. (2) Except as permitted in Sentence (3), where individual members of a built-up beam are butted together to form a joint, the joint shall occur over….
  • Floor joists carrying roof loads may cantilever 400 mm for 38 x 184 joists and 600 mm for 38 x 235 or deeper OBC Div. B 9.23.9.9.OBC Div. B 9.23.9.9. Cantilevered Floor Joists(1) Floor joists supporting roof loads shall not be cantilevered more than 400 mm beyond their supports where 38 mm by 184 mm joists are used and not more than 600 mm beyond their supports where 38 mm by 235 mm or larger joists are used. (2) The cantilevered portions referred to in Sentence (1) shall not support floor….
  • A loadbearing wall at right angles to the joists must sit within 900 mm of the joist support if it carries no floor, and within 600 mm if it carries a floor, unless the joists are designed for it OBC Div. B 9.23.9.8.OBC Div. B 9.23.9.8. Support of Walls(1) Non-loadbearing walls parallel to the floor joists shall be supported by joists beneath the wall or on blocking between the joists. (2) Blocking referred to in Sentence (1) for the support of non-loadbearing walls shall be (a) not less than 38 mm by 89 mm lumber, and (b) except as required for the fastening of….

Studs. Stud size and spacing come from Table 9.23.10.1.OBC Div. B Table 9.23.10.1. Size and Spacing of Studs — Forming Part of Sentence 9.23.10.1.(1)Table 9.23.10.1. Size and Spacing of Studs — Forming Part of Sentence 9.23.10.1.(1) Type of Wall | Supported Loads (including dead loads) | Minimum Stud Size, mm | Maximum Stud Spacing, mm | Maximum Unsupported Height, m Interior | No load | 38 × 38 | 400 | 2.4 Interior | No load | 38 × 89 flat[1] | 400 | 3.6 Interior…. For exterior walls:

Load carried 38 x 89 studs 38 x 140 studs
Roof only 600 mm, 3.0 m high
Roof plus one floor 400 mm 600 mm
Roof plus 2 floors 300 mm (or 64 x 89 at 400 mm)

Studs run full storey height, with splices only by structural finger-jointing OBC Div. B 9.23.10.4.OBC Div. B 9.23.10.4. Continuity of Studs(1) Wall studs shall be continuous for the full storey height except at openings and shall not be spliced except by finger-jointing with a structural adhesive. (See Note A-9.23.10.4.(1)). At openings, use tripled studs each side if the lintel is longer than 3 m, and doubled studs if it is 3 m or less OBC Div. B 9.23.10.6.OBC Div. B 9.23.10.6. Studs at Sides of Openings(1) Where the lintel spanning the opening is more than 3 m long, studs shall be tripled on each side of the opening so that (a) the two inner studs on each side extend from the bottom of the supported lintel to the top of the bottom wall plate, and (b) the outer stud on each side extends from the bottom of the top….

Lintels come from Tables 9.23.4.2.-L and 9.23.12.3.-A to -D. These tables apply only to residential buildings with studs larger than 38 x 64, joist spans up to 4.9 m and truss spans up to 9.8 m OBC Div. B 9.23.12.3.OBC Div. B 9.23.12.3. Lintel Spans and Sizes(1) Spans and sizes of wood lintels shall conform to the spans shown in Span Tables 9.23.4.2.-L and 9.23.12.3.-A to 9.23.12.3.-D (a) for buildings of residential occupancy, (b) where the wall studs exceed 38 mm by 64 mm in size, (c) where the spans of supported joists do not exceed 4.9 m, and (d) where the spans of….

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Bracing, roof framing and sheathing

Bracing. In low to moderate hazard locations (S_a(0.2) of 0.70 or less and HWP under 0.80 kPa), sheathing, panel cladding or interior panel finishes provide the bracing OBC Div. B 9.23.13.1.OBC Div. B 9.23.13.1. Requirements for Low to Moderate Wind and Seismic Forces(1) This Article applies in locations where the seismic spectral acceleration, S_a(0.2) , is not more than 0.70 and the 1-in-50 hourly wind pressure is less than 0.80 kPa. (2) Bracing to resist lateral loads shall be designed and constructed as follows: (a) exterior walls shall be (i) clad with panel-type cladding in…. Higher hazards need braced wall bands. These are full storey height, no more than 1.2 m wide, and aligned between storeys OBC Div. B 9.23.13.4.OBC Div. B 9.23.13.4. Braced Wall Bands(1) Braced wall bands shall (a) be full storey height, (b) be not more than 1.2 m wide, (c) lap at both ends with another braced wall band, (d) be aligned with braced wall bands on storeys above and below, and (e) conform to the spacing and dimensions given in Table 9.23.13.5. (2) The perimeter of the building shall….

Ridge support. Rafters need ridge support from a loadbearing wall or a ridge beam with 89 mm of bearing. One exception: on roofs of 1 in 3 or steeper, the lower ends of the rafters may instead be tied, for example by ceiling joists nailed to every rafter OBC Div. B 9.23.14.8.OBC Div. B 9.23.14.8. Ridge Support(1) Except as provided in Sentence (4), roof rafters and joists shall be supported at the ridge of the roof by (a) a loadbearing wall extending from the ridge to suitable bearing, or (b) a ridge beam supported by not less than 89 mm length of bearing. (2) Except as provided in Sentence (3), the ridge beam referred to….

Subfloor OBC Div. B 9.23.15.5.OBC Div. B 9.23.15.5. Subfloor Thickness or Rating(1) Except as provided in Sentences (2) and (3), subfloors shall conform to Table 9.23.15.5.-A or 9.23.15.5.-B. (2) Where the finished flooring consists of not less than 19 mm matched wood strip flooring laid at right angles to joists spaced not more than 600 mm o.c., subflooring shall be permitted to consist of not…. Plywood or O-2 OSB is 15.5 mm thick at 400 and 500 mm support spacing, and 18.5 mm at 600 mm.

Roof sheathing OBC Div. B 9.23.16.7.OBC Div. B 9.23.16.7. Thickness or Rating(1) The thickness or rating of roof sheathing on a flat roof used as a walking deck shall conform to either Table 9.23.15.5.-A or 9.23.15.5.-B for subfloors. (2) The thickness or rating of roof sheathing on a roof not used as a walking deck shall conform to either Table 9.23.16.7.-A or Table 9.23.16.7.-B. (3)…. Plywood at 600 mm is 9.5 mm with edges supported, or 12.5 mm with edges unsupported.

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Sheet steel studs (9.24)

Section 9.24 covers non-loadbearing steel studs only. Loadbearing steel studs are designed to Part 4 OBC Div. B 9.24.1.1.OBC Div. B 9.24.1.1. Application(1) This Section applies to sheet steel study for use in non-loadbearing exterior and interior walls. (2) Where loadbearing steel studs are used, they shall be designed in conformance with Part 4.. The main rules:

  • Interior studs are at least 0.46 mm thick.
  • Runners are as thick as the studs, with 30 mm flanges.
  • Runners are fastened at no more than 600 mm o.c. in interior walls and 300 mm o.c. in exterior walls OBC Div. B 9.24.3.1.OBC Div. B 9.24.3.1. Installation of Runners(1) Runners shall be provided at the tops and bottoms of walls. (2) Runners required in Sentence (1) shall be securely attached to the building at approximately 50 mm from the ends, and at intervals of not more than 600 mm o.c. for interior walls and 300 mm o.c. for exterior walls. (3) Fasteners used for attachment….
  • In fire-rated walls, leave at least a 12 mm gap at the top runner so the studs can expand OBC Div. B 9.24.3.2.OBC Div. B 9.24.3.2. Fire-Rated Walls(1) Steel studs used in walls required to have a fire-resistance rating shall be installed so that there is not less than a 12 mm clearance between the top of the stud and the top of the runner to allow for expansion in the event of fire. (2) Except as provided in Article 9.24.3.6., studs in walls referred to in….

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Chapter review

Chapter at a glance

One line per section: the idea to carry into the exam. Then the answers that most often catch candidates out.

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Questions on Wood-frame and steel stud construction (Part 9), in the exam format, every answer explained and cited to its article. Sign in to start; a free account gets the free questions.

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Code cited in this chapter

Based on the official 2024 Building Code Compendium on ontario.ca.

© King's Printer for Ontario, 2024. Reproduced with permission.

  • OBC Div. B 9.23.4.2. Spans for Joists, Rafters and Beams

    (1)Except as required in Sentence (2) and Article 9.23.14.10., spans for wood joists and rafters shall conform to the spans shown in Span Tables 9.23.4.2.-A to 9.23.4.2-G for the uniform live loads shown in the Tables. (See Article 9.4.2.2.)

    (2)Spans for floor joists that are not selected from Span Tables 9.23.4.2.-A and 9.23.4.2-B and that are required to be designed for the same loading conditions, shall not exceed the design requirements for uniform loading and vibration criteria. (See Note A-9.23.4.2.(2))

    (3)Spans for built-up wood and glued-laminated timber floor beams shall conform to the spans in Span Tables 9.23.4.2.-H to 9.23.4.2-K. (See Article 9.4.2.2.)

    (4)Spans for roof ridge beams shall conform to the spans in Span Table 9.23.4.2.-L for the uniform snow load shown. (See Articles 9.4.2.2. and 9.23.14.8.)

    Open OBC Div. B 9.23.4.2. in the code viewer
  • OBC Div. B 9.23.4.1. Application

    (1)Spans provided in this Subsection for joists, beams and lintels supporting floors shall apply only where

    (a)the floors serve residential areas as described in Table 4.1.5.3., or

    (b)the uniformly distributed live load on the floors does not exceed that specified for residential areas as described in Table 4.1.5.3.

    (2)Spans for joists, beams and lintels supporting floors shall be determined according to Subsection 4.1.3. where the supported floors

    (a)serve other than residential areas, or

    (b)support a uniform live load in excess of that specified for residential areas.

    Open OBC Div. B 9.23.4.1. in the code viewer
  • OBC Div. B Table 9.23.4.2-A. Maximum Spans for Floor Joists – General Cases with Strapping[2]

    Table 9.23.4.2.-A — Maximum Spans for Floor Joists – General Cases with Strapping[2] Forming Part of Sentences 9.23.2.8.(1), 9.23.4.2.(1) and (2), 9.23.4.4.(1) and 9.23.9.4.(1) to (3) Commercial Designation | Grade | Joist Size, mm | Joist Spacing, 300 mm | Joist Spacing, 400 mm | Joist Spacing, 600 mm Douglas Fir – Larch[3] | Select Structural | 38 × 89 | 2.13 m | 1.97 m | 1.73 m Douglas Fir – Larch[3] | Select Structural | 38 × 140 | 3.23 m | 3.07 m | 2.73 m Douglas Fir – Larch[3] | Select Structural | 38 × 184 | 3.88 m | 3.69 m | 3.51 m Douglas Fir – Larch[3] | Select Structural | 38 × 235 | 4.57 m | 4.34 m | 4.13 m Douglas Fir – Larch[3] | Select Structural | 38 × 286 | 5.21 m | 4.95 m | 4.71 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 89 | 2.00 m | 1.85 m | 1.66 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 140 | 3.09 m | 2.91 m | 2.62 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 184 | 3.71 m | 3.53 m | 3.36 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 235 | 4.38 m | 4.16 m | 3.96 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 286 | 4.99 m | 4.75 m | 4.52 m Douglas Fir – Larch[3] | No. 3 | 38 × 89 | 1.90 m | 1.69 m | 1.38 m Douglas Fir – Larch[3] | No. 3 | 38 × 140 | 2.78 m | 2.41 m | 1.97 m Douglas Fir – Larch[3] | No. 3 | 38 × 184 | 3.38 m | 2.93 m | 2.39 m Douglas Fir – Larch[3] | No. 3 | 38 × 235 | 4.14 m | 3.58 m | 2.93 m Douglas Fir – Larch[3] | No. 3 | 38 × 286 | 4.80 m | 4.16 m | 3.39 m Douglas Fir – Larch[3] | Construction | 38 × 89 | 1.90 m | 1.77 m | 1.61 m Douglas Fir – Larch[3] | Standard | 38 × 89 | 1.81 m | 1.63 m | 1.33 m Hem – Fir[4] | Select Structural | 38 × 89 | 2.08 m | 1.93 m | 1.71 m Hem – Fir[4] | Select Structural | 38 × 140 | 3.18 m | 3.03 m | 2.69 m Hem – Fir[4] | Select Structural | 38 × 184 | 3.82 m | 3.64 m | 3.46 m Hem – Fir[4] | Select Structural | 38 × 235 | 4.50 m | 4.28 m | 4.08 m Hem – Fir[4] | Select Structural | 38 × 286 | 5.14 m | 4.89 m | 4.65 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 89 | 2.00 m | 1.85 m | 1.66 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 140 | 3.09 m | 2.91 m | 2.62 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 184 | 3.71 m | 3.53 m | 3.36 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 235 | 4.38 m | 4.16 m | 3.96 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 286 | 4.99 m | 4.75 m | 4.52 m Hem – Fir[4] | No. 3 | 38 × 89 | 1.90 m | 1.77 m | 1.61 m Hem – Fir[4] | No. 3 | 38 × 140 | 2.99 m | 2.78 m | 2.43 m Hem – Fir[4] | No. 3 | 38 × 184 | 3.60 m | 3.42 m | 2.95 m Hem – Fir[4] | No. 3 | 38 × 235 | 4.24 m | 4.03 m | 3.61 m Hem – Fir[4] | No. 3 | 38 × 286 | 4.84 m | 4.60 m | 4.19 m Hem – Fir[4] | Construction | 38 × 89 | 1.90 m | 1.77 m | 1.61 m Hem – Fir[4] | Standard | 38 × 89 | 1.81 m | 1.68 m | 1.39 m Spruce – Pine – Fir[5] | Select Structural | 38 × 89 | 1.95 m | 1.81 m | 1.64 m Spruce – Pine – Fir[5] | Select Structural | 38 × 140 | 3.05 m | 2.85 m | 2.57 m Spruce – Pine – Fir[5] | Select Structural | 38 × 184 | 3.66 m | 3.48 m | 3.31 m Spruce – Pine – Fir[5] | Select Structural | 38 × 235 | 4.31 m | 4.10 m | 3.90 m Spruce – Pine – Fir[5] | Select Structural | 38 × 286 | 4.91 m | 4.67 m | 4.45 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 89 | 1.86 m | 1.72 m | 1.58 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 140 | 2.92 m | 2.71 m | 2.49 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 184 | 3.54 m | 3.36 m | 3.20 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 235 | 4.17 m | 3.96 m | 3.77 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 286 | 4.75 m | 4.52 m | 4.30 m Spruce – Pine – Fir[5] | No. 3 | 38 × 89 | 1.81 m | 1.68 m | 1.55 m Spruce – Pine – Fir[5] | No. 3 | 38 × 140 | 2.84 m | 2.64 m | 2.43 m Spruce – Pine – Fir[5] | No. 3 | 38 × 184 | 3.47 m | 3.30 m | 2.95 m Spruce – Pine – Fir[5] | No. 3 | 38 × 235 | 4.09 m | 3.89 m | 3.61 m Spruce – Pine – Fir[5] | No. 3 | 38 × 286 | 4.67 m | 4.44 m | 4.19 m Spruce – Pine – Fir[5] | Construction | 38 × 89 | 1.81 m | 1.68 m | 1.55 m Spruce – Pine – Fir[5] | Standard | 38 × 89 | 1.70 m | 1.58 m | 1.44 m Northern Species[6] | Select Structural | 38 × 89 | 1.65 m | 1.53 m | 1.42 m Northern Species[6] | Select Structural | 38 × 140 | 2.59 m | 2.41 m | 2.24 m Northern Species[6] | Select Structural | 38 × 184 | 3.27 m | 3.11 m | 2.94 m Northern Species[6] | Select Structural | 38 × 235 | 3.85 m | 3.66 m | 3.48 m Northern Species[6] | Select Structural | 38 × 286 | 4.39 m | 4.18 m | 3.97 m Northern Species[6] | No. 1 and No. 2 | 38 × 89 | 1.59 m | 1.48 m | 1.37 m Northern Species[6] | No. 1 and No. 2 | 38 × 140 | 2.51 m | 2.33 m | 2.16 m Northern Species[6] | No. 1 and No. 2 | 38 × 184 | 3.19 m | 3.04 m | 2.84 m Northern Species[6] | No. 1 and No. 2 | 38 × 235 | 3.76 m | 3.58 m | 3.41 m Northern Species[6] | No. 1 and No. 2 | 38 × 286 | 4.29 m | 4.08 m | 3.88 m Northern Species[6] | No. 3 | 38 × 89 | 1.54 m | 1.43 m | 1.32 m Northern Species[6] | No. 3 | 38 × 140 | 2.42 m | 2.24 m | 1.94 m Northern Species[6] | No. 3 | 38 × 184 | 3.12 m | 2.90 m | 2.37 m Northern Species[6] | No. 3 | 38 × 235 | 3.67 m | 3.49 m | 2.89 m Northern Species[6] | No. 3 | 38 × 286 | 4.19 m | 3.98 m | 3.36 m Northern Species[6] | Construction | 38 × 89 | 1.54 m | 1.43 m | 1.32 m Northern Species[6] | Standard | 38 × 89 | 1.48 m | 1.37 m | 1.15 m Table 9.23.4.2.-A (continued) — Maximum Spans for Floor Joists – General Cases with Bridging Commercial Designation | Grade | Joist Size, mm | Joist Spacing, 300 mm | Joist Spacing, 400 mm | Joist Spacing, 600 mm Douglas Fir – Larch[3] | Select Structural | 38 × 89 | 2.19 m | 1.99 m | 1.73 m Douglas Fir – Larch[3] | Select Structural | 38 × 140 | 3.44 m | 3.12 m | 2.73 m Douglas Fir – Larch[3] | Select Structural | 38 × 184 | 4.18 m | 3.92 m | 3.59 m Douglas Fir – Larch[3] | Select Structural | 38 × 235 | 4.86 m | 4.57 m | 4.29 m Douglas Fir – Larch[3] | Select Structural | 38 × 286 | 5.49 m | 5.16 m | 4.85 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 89 | 2.09 m | 1.90 m | 1.66 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 140 | 3.29 m | 2.99 m | 2.62 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 184 | 4.00 m | 3.76 m | 3.44 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 235 | 4.66 m | 4.38 m | 4.11 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 286 | 5.26 m | 4.94 m | 4.65 m Douglas Fir – Larch[3] | No. 3 | 38 × 89 | 1.95 m | 1.69 m | 1.38 m Douglas Fir – Larch[3] | No. 3 | 38 × 140 | 2.78 m | 2.41 m | 1.97 m Douglas Fir – Larch[3] | No. 3 | 38 × 184 | 3.38 m | 2.93 m | 2.39 m Douglas Fir – Larch[3] | No. 3 | 38 × 235 | 4.14 m | 3.58 m | 2.93 m Douglas Fir – Larch[3] | No. 3 | 38 × 286 | 4.80 m | 4.16 m | 3.39 m Douglas Fir – Larch[3] | Construction | 38 × 89 | 2.03 m | 1.84 m | 1.61 m Douglas Fir – Larch[3] | Standard | 38 × 89 | 1.88 m | 1.63 m | 1.33 m Hem – Fir[4] | Select Structural | 38 × 89 | 2.16 m | 1.96 m | 1.71 m Hem – Fir[4] | Select Structural | 38 × 140 | 3.39 m | 3.08 m | 2.69 m Hem – Fir[4] | Select Structural | 38 × 184 | 4.12 m | 3.87 m | 3.54 m Hem – Fir[4] | Select Structural | 38 × 235 | 4.80 m | 4.51 m | 4.23 m Hem – Fir[4] | Select Structural | 38 × 286 | 5.42 m | 5.09 m | 4.78 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 89 | 2.09 m | 1.90 m | 1.66 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 140 | 3.29 m | 2.99 m | 2.62 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 184 | 4.00 m | 3.76 m | 3.44 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 235 | 4.66 m | 4.38 m | 4.11 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 286 | 5.26 m | 4.94 m | 4.65 m Hem – Fir[4] | No. 3 | 38 × 89 | 2.03 m | 1.84 m | 1.61 m Hem – Fir[4] | No. 3 | 38 × 140 | 3.19 m | 2.90 m | 2.43 m Hem – Fir[4] | No. 3 | 38 × 184 | 3.88 m | 3.61 m | 2.95 m Hem – Fir[4] | No. 3 | 38 × 235 | 4.51 m | 4.24 m | 3.61 m Hem – Fir[4] | No. 3 | 38 × 286 | 5.10 m | 4.79 m | 4.19 m Hem – Fir[4] | Construction | 38 × 89 | 2.03 m | 1.84 m | 1.61 m Hem – Fir[4] | Standard | 38 × 89 | 1.96 m | 1.71 m | 1.39 m Spruce – Pine – Fir[5] | Select Structural | 38 × 89 | 2.06 m | 1.87 m | 1.64 m Spruce – Pine – Fir[5] | Select Structural | 38 × 140 | 3.24 m | 2.95 m | 2.57 m Spruce – Pine – Fir[5] | Select Structural | 38 × 184 | 3.94 m | 3.70 m | 3.38 m Spruce – Pine – Fir[5] | Select Structural | 38 × 235 | 4.59 m | 4.31 m | 4.05 m Spruce – Pine – Fir[5] | Select Structural | 38 × 286 | 5.18 m | 4.87 m | 4.57 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 89 | 1.99 m | 1.81 m | 1.58 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 140 | 3.14 m | 2.85 m | 2.49 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 184 | 3.81 m | 3.58 m | 3.27 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 235 | 4.44 m | 4.17 m | 3.92 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 286 | 5.01 m | 4.71 m | 4.42 m Spruce – Pine – Fir[5] | No. 3 | 38 × 89 | 1.96 m | 1.78 m | 1.55 m Spruce – Pine – Fir[5] | No. 3 | 38 × 140 | 3.08 m | 2.80 m | 2.43 m Spruce – Pine – Fir[5] | No. 3 | 38 × 184 | 3.74 m | 3.52 m | 2.95 m Spruce – Pine – Fir[5] | No. 3 | 38 × 235 | 4.36 m | 4.09 m | 3.61 m Spruce – Pine – Fir[5] | No. 3 | 38 × 286 | 4.92 m | 4.62 m | 4.19 m Spruce – Pine – Fir[5] | Construction | 38 × 89 | 1.96 m | 1.78 m | 1.55 m Spruce – Pine – Fir[5] | Standard | 38 × 89 | 1.88 m | 1.71 m | 1.44 m Northern Species[6] | Select Structural | 38 × 89 | 1.84 m | 1.68 m | 1.46 m Northern Species[6] | Select Structural | 38 × 140 | 2.90 m | 2.63 m | 2.30 m Northern Species[6] | Select Structural | 38 × 184 | 3.52 m | 3.31 m | 3.03 m Northern Species[6] | Select Structural | 38 × 235 | 4.10 m | 3.85 m | 3.62 m Northern Species[6] | Select Structural | 38 × 286 | 4.63 m | 4.35 m | 4.09 m Northern Species[6] | No. 1 and No. 2 | 38 × 89 | 1.80 m | 1.64 m | 1.43 m Northern Species[6] | No. 1 and No. 2 | 38 × 140 | 2.83 m | 2.57 m | 2.25 m Northern Species[6] | No. 1 and No. 2 | 38 × 184 | 3.44 m | 3.23 m | 2.96 m Northern Species[6] | No. 1 and No. 2 | 38 × 235 | 4.01 m | 3.77 m | 3.54 m Northern Species[6] | No. 1 and No. 2 | 38 × 286 | 4.53 m | 4.25 m | 4.00 m Northern Species[6] | No. 3 | 38 × 89 | 1.74 m | 1.57 m | 1.36 m Northern Species[6] | No. 3 | 38 × 140 | 2.74 m | 2.38 m | 1.94 m Northern Species[6] | No. 3 | 38 × 184 | 3.35 m | 2.90 m | 2.37 m Northern Species[6] | No. 3 | 38 × 235 | 3.91 m | 3.54 m | 2.89 m Northern Species[6] | No. 3 | 38 × 286 | 4.42 m | 4.11 m | 3.36 m Northern Species[6] | Construction | 38 × 89 | 1.74 m | 1.57 m | 1.40 m Northern Species[6] | Standard | 38 × 89 | 1.63 m | 1.41 m | 1.15 m Table 9.23.4.2.-A (continued) — Maximum Spans for Floor Joists – General Cases with Strapping[2] and Bridging Commercial Designation | Grade | Joist Size, mm | Joist Spacing, 300 mm | Joist Spacing, 400 mm | Joist Spacing, 600 mm Douglas Fir – Larch[3] | Select Structural | 38 × 89 | 2.19 m | 1.99 m | 1.73 m Douglas Fir – Larch[3] | Select Structural | 38 × 140 | 3.44 m | 3.12 m | 2.73 m Douglas Fir – Larch[3] | Select Structural | 38 × 184 | 4.37 m | 4.07 m | 3.59 m Douglas Fir – Larch[3] | Select Structural | 38 × 235 | 5.05 m | 4.70 m | 4.39 m Douglas Fir – Larch[3] | Select Structural | 38 × 286 | 5.66 m | 5.28 m | 4.92 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 89 | 2.09 m | 1.90 m | 1.66 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 140 | 3.29 m | 2.99 m | 2.62 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 184 | 4.19 m | 3.90 m | 3.44 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 235 | 4.84 m | 4.51 m | 4.20 m Douglas Fir – Larch[3] | No. 1 and No. 2 | 38 × 286 | 5.43 m | 5.06 m | 4.72 m Douglas Fir – Larch[3] | No. 3 | 38 × 89 | 1.95 m | 1.69 m | 1.38 m Douglas Fir – Larch[3] | No. 3 | 38 × 140 | 2.78 m | 2.41 m | 1.97 m Douglas Fir – Larch[3] | No. 3 | 38 × 184 | 3.38 m | 2.93 m | 2.39 m Douglas Fir – Larch[3] | No. 3 | 38 × 235 | 4.14 m | 3.58 m | 2.93 m Douglas Fir – Larch[3] | No. 3 | 38 × 286 | 4.80 m | 4.16 m | 3.39 m Douglas Fir – Larch[3] | Construction | 38 × 89 | 2.03 m | 1.84 m | 1.61 m Douglas Fir – Larch[3] | Standard | 38 × 89 | 1.88 m | 1.63 m | 1.33 m Hem – Fir[4] | Select Structural | 38 × 89 | 2.16 m | 1.96 m | 1.71 m Hem – Fir[4] | Select Structural | 38 × 140 | 3.39 m | 3.08 m | 2.69 m Hem – Fir[4] | Select Structural | 38 × 184 | 4.31 m | 4.02 m | 3.54 m Hem – Fir[4] | Select Structural | 38 × 235 | 4.98 m | 4.64 m | 4.33 m Hem – Fir[4] | Select Structural | 38 × 286 | 5.59 m | 5.21 m | 4.86 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 89 | 2.09 m | 1.90 m | 1.66 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 140 | 3.29 m | 2.99 m | 2.62 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 184 | 4.19 m | 3.90 m | 3.44 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 235 | 4.84 m | 4.51 m | 4.20 m Hem – Fir[4] | No. 1 and No. 2 | 38 × 286 | 5.43 m | 5.06 m | 4.72 m Hem – Fir[4] | No. 3 | 38 × 89 | 2.03 m | 1.84 m | 1.61 m Hem – Fir[4] | No. 3 | 38 × 140 | 3.19 m | 2.90 m | 2.43 m Hem – Fir[4] | No. 3 | 38 × 184 | 4.06 m | 3.61 m | 2.95 m Hem – Fir[4] | No. 3 | 38 × 235 | 4.68 m | 4.37 m | 3.61 m Hem – Fir[4] | No. 3 | 38 × 286 | 5.26 m | 4.90 m | 4.19 m Hem – Fir[4] | Construction | 38 × 89 | 2.03 m | 1.84 m | 1.61 m Hem – Fir[4] | Standard | 38 × 89 | 1.96 m | 1.71 m | 1.39 m Spruce – Pine – Fir[5] | Select Structural | 38 × 89 | 2.06 m | 1.87 m | 1.64 m Spruce – Pine – Fir[5] | Select Structural | 38 × 140 | 3.24 m | 2.95 m | 2.57 m Spruce – Pine – Fir[5] | Select Structural | 38 × 184 | 4.12 m | 3.84 m | 3.38 m Spruce – Pine – Fir[5] | Select Structural | 38 × 235 | 4.76 m | 4.44 m | 4.14 m Spruce – Pine – Fir[5] | Select Structural | 38 × 286 | 5.34 m | 4.98 m | 4.64 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 89 | 1.99 m | 1.81 m | 1.58 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 140 | 3.14 m | 2.85 m | 2.49 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 184 | 3.99 m | 3.72 m | 3.27 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 235 | 4.60 m | 4.29 m | 4.00 m Spruce – Pine – Fir[5] | No. 1 and No. 2 | 38 × 286 | 5.17 m | 4.82 m | 4.49 m Spruce – Pine – Fir[5] | No. 3 | 38 × 89 | 1.96 m | 1.78 m | 1.55 m Spruce – Pine – Fir[5] | No. 3 | 38 × 140 | 3.08 m | 2.80 m | 2.43 m Spruce – Pine – Fir[5] | No. 3 | 38 × 184 | 3.92 m | 3.61 m | 2.95 m Spruce – Pine – Fir[5] | No. 3 | 38 × 235 | 4.52 m | 4.22 m | 3.61 m Spruce – Pine – Fir[5] | No. 3 | 38 × 286 | 5.08 m | 4.73 m | 4.19 m Spruce – Pine – Fir[5] | Construction | 38 × 89 | 1.96 m | 1.78 m | 1.55 m Spruce – Pine – Fir[5] | Standard | 38 × 89 | 1.88 m | 1.71 m | 1.44 m Northern Species[6] | Select Structural | 38 × 89 | 1.84 m | 1.68 m | 1.46 m Northern Species[6] | Select Structural | 38 × 140 | 2.90 m | 2.63 m | 2.30 m Northern Species[6] | Select Structural | 38 × 184 | 3.69 m | 3.44 m | 3.03 m Northern Species[6] | Select Structural | 38 × 235 | 4.26 m | 3.97 m | 3.70 m Northern Species[6] | Select Structural | 38 × 286 | 4.78 m | 4.45 m | 4.15 m Northern Species[6] | No. 1 and No. 2 | 38 × 89 | 1.80 m | 1.64 m | 1.43 m Northern Species[6] | No. 1 and No. 2 | 38 × 140 | 2.83 m | 2.57 m | 2.25 m Northern Species[6] | No. 1 and No. 2 | 38 × 184 | 3.60 m | 3.36 m | 2.96 m Northern Species[6] | No. 1 and No. 2 | 38 × 235 | 4.16 m | 3.88 m | 3.62 m Northern Species[6] | No. 1 and No. 2 | 38 × 286 | 4.67 m | 4.35 m | 4.06 m Northern Species[6] | No. 3 | 38 × 89 | 1.76 m | 1.60 m | 1.36 m Northern Species[6] | No. 3 | 38 × 140 | 2.75 m | 2.38 m | 1.94 m Northern Species[6] | No. 3 | 38 × 184 | 3.35 m | 2.90 m | 2.37 m Northern Species[6] | No. 3 | 38 × 235 | 4.06 m | 3.54 m | 2.89 m Northern Species[6] | No. 3 | 38 × 286 | 4.55 m | 4.11 m | 3.36 m Northern Species[6] | Construction | 38 × 89 | 1.76 m | 1.60 m | 1.40 m Northern Species[6] | Standard | 38 × 89 | 1.63 m | 1.41 m | 1.15 m Notes to Table 9.23.4.2.-A: (1) Spans apply only where the floors serve residential areas as described in Table 4.1.5.3., or the uniformly distributed live load on the floor does not exceed that specified for residential areas as described in Table 4.1.5.3. (2) See Sentence 9.23.9.4.(5) for alternatives to strapping. (3) Includes Douglas Fir and Western Larch. (4) Includes Western Hemlock and Amabilis Fir. (5) Includes Spruce (all species except Coast Sitka Spruce), Jack Pine, Lodgepole Pine, Balsam Fir and Alpine Fir. (6) Includes any Canadian Species covered by the NLGA Standard Grading Rules.

    Open OBC Div. B Table 9.23.4.2-A. in the code viewer
  • OBC Div. B Table 9.23.4.2-F. Maximum Spans for Roof Rafters – Specified Roof Snow Loads 1.0 kPa

    Table 9.23.4.2.-F — Maximum Spans for Roof Rafters – Specified Roof Snow Loads 1.0 kPa Forming Part of Sentences 9.23.2.8.(1), 9.23.4.2.(1), 9.23.4.5.(1) and 9.23.14.10.(2) Commercial Designation | Grade | Rafter Size, mm | Rafter Spacing 300 mm | Rafter Spacing 400 mm | Rafter Spacing 600 mm Douglas Fir – Larch[1] | Select Structural | 38 × 89 | 3.41 m | 3.10 m | 2.71 m Douglas Fir – Larch[1] | Select Structural | 38 × 140 | 5.37 m | 4.88 m | 4.26 m Douglas Fir – Larch[1] | Select Structural | 38 × 184 | 7.05 m | 6.41 m | 5.60 m Douglas Fir – Larch[1] | Select Structural | 38 × 235 | 9.01 m | 8.18 m | 7.15 m Douglas Fir – Larch[1] | Select Structural | 38 × 286 | 10.96 m | 9.96 m | 8.70 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 89 | 3.27 m | 2.97 m | 2.59 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 140 | 5.14 m | 4.67 m | 3.95 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 184 | 6.76 m | 5.88 m | 4.80 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 235 | 8.30 m | 7.19 m | 5.87 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 286 | 9.63 m | 8.34 m | 6.81 m Douglas Fir – Larch[1] | No. 3 | 38 × 89 | 2.65 m | 2.30 m | 1.87 m Douglas Fir – Larch[1] | No. 3 | 38 × 140 | 3.78 m | 3.28 m | 2.68 m Douglas Fir – Larch[1] | No. 3 | 38 × 184 | 4.61 m | 3.99 m | 3.26 m Douglas Fir – Larch[1] | No. 3 | 38 × 235 | 5.63 m | 4.88 m | 3.98 m Douglas Fir – Larch[1] | No. 3 | 38 × 286 | 6.53 m | 5.66 m | 4.62 m Douglas Fir – Larch[1] | Construction | 38 × 89 | 3.17 m | 2.88 m | 2.42 m Douglas Fir – Larch[1] | Standard | 38 × 89 | 2.56 m | 2.22 m | 1.81 m Hem – Fir[2] | Select Structural | 38 × 89 | 3.36 m | 3.06 m | 2.67 m Hem – Fir[2] | Select Structural | 38 × 140 | 5.29 m | 4.81 m | 4.20 m Hem – Fir[2] | Select Structural | 38 × 184 | 6.96 m | 6.32 m | 5.52 m Hem – Fir[2] | Select Structural | 38 × 235 | 8.88 m | 8.07 m | 7.05 m Hem – Fir[2] | Select Structural | 38 × 286 | 10.81 m | 9.82 m | 8.58 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 89 | 3.27 m | 2.97 m | 2.59 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 140 | 5.14 m | 4.67 m | 4.08 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 184 | 6.76 m | 6.14 m | 5.04 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 235 | 8.63 m | 7.54 m | 6.16 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 286 | 10.11 m | 8.75 m | 7.15 m Hem – Fir[2] | No. 3 | 38 × 89 | 3.17 m | 2.83 m | 2.31 m Hem – Fir[2] | No. 3 | 38 × 140 | 4.67 m | 4.04 m | 3.30 m Hem – Fir[2] | No. 3 | 38 × 184 | 5.68 m | 4.92 m | 4.02 m Hem – Fir[2] | No. 3 | 38 × 235 | 6.95 m | 6.02 m | 4.91 m Hem – Fir[2] | No. 3 | 38 × 286 | 8.06 m | 6.98 m | 5.70 m Hem – Fir[2] | Construction | 38 × 89 | 3.17 m | 2.88 m | 2.51 m Hem – Fir[2] | Standard | 38 × 89 | 2.68 m | 2.32 m | 1.90 m Spruce – Pine – Fir[3] | Select Structural | 38 × 89 | 3.22 m | 2.92 m | 2.55 m Spruce – Pine – Fir[3] | Select Structural | 38 × 140 | 5.06 m | 4.60 m | 4.02 m Spruce – Pine – Fir[3] | Select Structural | 38 × 184 | 6.65 m | 6.05 m | 5.28 m Spruce – Pine – Fir[3] | Select Structural | 38 × 235 | 8.50 m | 7.72 m | 6.74 m Spruce – Pine – Fir[3] | Select Structural | 38 × 286 | 10.34 m | 9.40 m | 8.21 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 89 | 3.11 m | 2.83 m | 2.47 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 140 | 4.90 m | 4.45 m | 3.89 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 184 | 6.44 m | 5.85 m | 5.11 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 235 | 8.22 m | 7.47 m | 6.38 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 286 | 10.00 m | 9.06 m | 7.40 m Spruce – Pine – Fir[3] | No. 3 | 38 × 89 | 3.06 m | 2.78 m | 2.31 m Spruce – Pine – Fir[3] | No. 3 | 38 × 140 | 4.67 m | 4.04 m | 3.30 m Spruce – Pine – Fir[3] | No. 3 | 38 × 184 | 5.68 m | 4.92 m | 4.02 m Spruce – Pine – Fir[3] | No. 3 | 38 × 235 | 6.95 m | 6.02 m | 4.91 m Spruce – Pine – Fir[3] | No. 3 | 38 × 286 | 8.06 m | 6.98 m | 5.70 m Spruce – Pine – Fir[3] | Construction | 38 × 89 | 3.06 m | 2.78 m | 2.43 m Spruce – Pine – Fir[3] | Standard | 38 × 89 | 2.78 m | 2.41 m | 1.97 m Northern Species[4] | Select Structural | 38 × 89 | 2.88 m | 2.61 m | 2.28 m Northern Species[4] | Select Structural | 38 × 140 | 4.53 m | 4.11 m | 3.59 m Northern Species[4] | Select Structural | 38 × 184 | 5.95 m | 5.40 m | 4.72 m Northern Species[4] | Select Structural | 38 × 235 | 7.60 m | 6.90 m | 6.03 m Northern Species[4] | Select Structural | 38 × 286 | 9.25 m | 8.40 m | 7.01 m Northern Species[4] | No. 1 and No. 2 | 38 × 89 | 2.81 m | 2.55 m | 2.23 m Northern Species[4] | No. 1 and No. 2 | 38 × 140 | 4.42 m | 4.02 m | 3.44 m Northern Species[4] | No. 1 and No. 2 | 38 × 184 | 5.81 m | 5.13 m | 4.19 m Northern Species[4] | No. 1 and No. 2 | 38 × 235 | 7.24 m | 6.27 m | 5.12 m Northern Species[4] | No. 1 and No. 2 | 38 × 286 | 8.40 m | 7.27 m | 5.94 m Northern Species[4] | No. 3 | 38 × 89 | 2.62 m | 2.27 m | 1.85 m Northern Species[4] | No. 3 | 38 × 140 | 3.74 m | 3.24 m | 2.65 m Northern Species[4] | No. 3 | 38 × 184 | 4.56 m | 3.94 m | 3.22 m Northern Species[4] | No. 3 | 38 × 235 | 5.57 m | 4.82 m | 3.94 m Northern Species[4] | No. 3 | 38 × 286 | 6.46 m | 5.60 m | 4.57 m Northern Species[4] | Construction | 38 × 89 | 2.74 m | 2.49 m | 2.11 m Northern Species[4] | Standard | 38 × 89 | 2.22 m | 1.93 m | 1.57 m Table 9.23.4.2.-F (continued) — Maximum Spans for Roof Rafters – Specified Roof Snow Loads 1.5 kPa Commercial Designation | Grade | Rafter Size, mm | Rafter Spacing 300 mm | Rafter Spacing 400 mm | Rafter Spacing 600 mm Douglas Fir – Larch[1] | Select Structural | 38 × 89 | 2.98 m | 2.71 m | 2.37 m Douglas Fir – Larch[1] | Select Structural | 38 × 140 | 4.69 m | 4.26 m | 3.72 m Douglas Fir – Larch[1] | Select Structural | 38 × 184 | 6.16 m | 5.60 m | 4.89 m Douglas Fir – Larch[1] | Select Structural | 38 × 235 | 7.87 m | 7.15 m | 6.24 m Douglas Fir – Larch[1] | Select Structural | 38 × 286 | 9.58 m | 8.70 m | 7.40 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 89 | 2.86 m | 2.59 m | 2.27 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 140 | 4.49 m | 4.08 m | 3.34 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 184 | 5.74 m | 4.97 m | 4.06 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 235 | 7.02 m | 6.08 m | 4.96 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 286 | 8.14 m | 7.05 m | 5.76 m Douglas Fir – Larch[1] | No. 3 | 38 × 89 | 2.24 m | 1.94 m | 1.58 m Douglas Fir – Larch[1] | No. 3 | 38 × 140 | 3.20 m | 2.77 m | 2.26 m Douglas Fir – Larch[1] | No. 3 | 38 × 184 | 3.89 m | 3.37 m | 2.75 m Douglas Fir – Larch[1] | No. 3 | 38 × 235 | 4.76 m | 4.12 m | 3.37 m Douglas Fir – Larch[1] | No. 3 | 38 × 286 | 5.52 m | 4.78 m | 3.91 m Douglas Fir – Larch[1] | Construction | 38 × 89 | 2.77 m | 2.50 m | 2.04 m Douglas Fir – Larch[1] | Standard | 38 × 89 | 2.17 m | 1.88 m | 1.53 m Hem – Fir[2] | Select Structural | 38 × 89 | 2.94 m | 2.67 m | 2.33 m Hem – Fir[2] | Select Structural | 38 × 140 | 4.62 m | 4.20 m | 3.67 m Hem – Fir[2] | Select Structural | 38 × 184 | 6.08 m | 5.52 m | 4.82 m Hem – Fir[2] | Select Structural | 38 × 235 | 7.76 m | 7.05 m | 6.16 m Hem – Fir[2] | Select Structural | 38 × 286 | 9.45 m | 8.58 m | 7.28 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 89 | 2.86 m | 2.59 m | 2.27 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 140 | 4.49 m | 4.08 m | 3.50 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 184 | 5.90 m | 5.21 m | 4.26 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 235 | 7.36 m | 6.37 m | 5.20 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 286 | 8.54 m | 7.40 m | 6.04 m Hem – Fir[2] | No. 3 | 38 × 89 | 2.76 m | 2.39 m | 1.95 m Hem – Fir[2] | No. 3 | 38 × 140 | 3.95 m | 3.42 m | 2.79 m Hem – Fir[2] | No. 3 | 38 × 184 | 4.80 m | 4.16 m | 3.40 m Hem – Fir[2] | No. 3 | 38 × 235 | 5.87 m | 5.08 m | 4.15 m Hem – Fir[2] | No. 3 | 38 × 286 | 6.81 m | 5.90 m | 4.82 m Hem – Fir[2] | Construction | 38 × 89 | 2.77 m | 2.51 m | 2.14 m Hem – Fir[2] | Standard | 38 × 89 | 2.27 m | 1.96 m | 1.60 m Spruce – Pine – Fir[3] | Select Structural | 38 × 89 | 2.81 m | 2.55 m | 2.23 m Spruce – Pine – Fir[3] | Select Structural | 38 × 140 | 4.42 m | 4.02 m | 3.51 m Spruce – Pine – Fir[3] | Select Structural | 38 × 184 | 5.81 m | 5.28 m | 4.61 m Spruce – Pine – Fir[3] | Select Structural | 38 × 235 | 7.42 m | 6.74 m | 5.89 m Spruce – Pine – Fir[3] | Select Structural | 38 × 286 | 9.03 m | 8.21 m | 7.17 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 89 | 2.72 m | 2.47 m | 2.16 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 140 | 4.28 m | 3.89 m | 3.40 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 184 | 5.62 m | 5.11 m | 4.41 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 235 | 7.18 m | 6.52 m | 5.39 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 286 | 8.74 m | 7.66 m | 6.25 m Spruce – Pine – Fir[3] | No. 3 | 38 × 89 | 2.67 m | 2.39 m | 1.95 m Spruce – Pine – Fir[3] | No. 3 | 38 × 140 | 3.95 m | 3.42 m | 2.79 m Spruce – Pine – Fir[3] | No. 3 | 38 × 184 | 4.80 m | 4.16 m | 3.40 m Spruce – Pine – Fir[3] | No. 3 | 38 × 235 | 5.87 m | 5.08 m | 4.15 m Spruce – Pine – Fir[3] | No. 3 | 38 × 286 | 6.81 m | 5.90 m | 4.82 m Spruce – Pine – Fir[3] | Construction | 38 × 89 | 2.67 m | 2.43 m | 2.12 m Spruce – Pine – Fir[3] | Standard | 38 × 89 | 2.35 m | 2.04 m | 1.66 m Northern Species[4] | Select Structural | 38 × 89 | 2.51 m | 2.28 m | 1.99 m Northern Species[4] | Select Structural | 38 × 140 | 3.95 m | 3.59 m | 3.14 m Northern Species[4] | Select Structural | 38 × 184 | 5.20 m | 4.72 m | 4.12 m Northern Species[4] | Select Structural | 38 × 235 | 6.64 m | 6.03 m | 5.11 m Northern Species[4] | Select Structural | 38 × 286 | 8.08 m | 7.26 m | 5.93 m Northern Species[4] | No. 1 and No. 2 | 38 × 89 | 2.46 m | 2.23 m | 1.95 m Northern Species[4] | No. 1 and No. 2 | 38 × 140 | 3.86 m | 3.51 m | 2.91 m Northern Species[4] | No. 1 and No. 2 | 38 × 184 | 5.00 m | 4.33 m | 3.54 m Northern Species[4] | No. 1 and No. 2 | 38 × 235 | 6.12 m | 5.30 m | 4.33 m Northern Species[4] | No. 1 and No. 2 | 38 × 286 | 7.10 m | 6.15 m | 5.02 m Northern Species[4] | No. 3 | 38 × 89 | 2.22 m | 1.92 m | 1.57 m Northern Species[4] | No. 3 | 38 × 140 | 3.16 m | 2.74 m | 2.24 m Northern Species[4] | No. 3 | 38 × 184 | 3.85 m | 3.33 m | 2.72 m Northern Species[4] | No. 3 | 38 × 235 | 4.71 m | 4.08 m | 3.33 m Northern Species[4] | No. 3 | 38 × 286 | 5.46 m | 4.73 m | 3.86 m Northern Species[4] | Construction | 38 × 89 | 2.40 m | 2.18 m | 1.90 m Northern Species[4] | Standard | 38 × 89 | 1.88 m | 1.63 m | 1.33 m Table 9.23.4.2.-F (continued) — Maximum Spans for Roof Rafters – Specified Roof Snow Loads 2.0 kPa Commercial Designation | Grade | Rafter Size, mm | Rafter Spacing 300 mm | Rafter Spacing 400 mm | Rafter Spacing 600 mm Douglas Fir – Larch[1] | Select Structural | 38 × 89 | 2.71 m | 2.46 m | 2.15 m Douglas Fir – Larch[1] | Select Structural | 38 × 140 | 4.26 m | 3.87 m | 3.38 m Douglas Fir – Larch[1] | Select Structural | 38 × 184 | 5.60 m | 5.09 m | 4.44 m Douglas Fir – Larch[1] | Select Structural | 38 × 235 | 7.15 m | 6.49 m | 5.62 m Douglas Fir – Larch[1] | Select Structural | 38 × 286 | 8.70 m | 7.90 m | 6.52 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 89 | 2.59 m | 2.36 m | 2.06 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 140 | 4.08 m | 3.60 m | 2.94 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 184 | 5.06 m | 4.38 m | 3.58 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 235 | 6.19 m | 5.36 m | 4.38 m Douglas Fir – Larch[1] | No. 1 and No. 2 | 38 × 286 | 7.18 m | 6.22 m | 5.08 m Douglas Fir – Larch[1] | No. 3 | 38 × 89 | 1.98 m | 1.71 m | 1.40 m Douglas Fir – Larch[1] | No. 3 | 38 × 140 | 2.82 m | 2.44 m | 1.99 m Douglas Fir – Larch[1] | No. 3 | 38 × 184 | 3.43 m | 2.97 m | 2.43 m Douglas Fir – Larch[1] | No. 3 | 38 × 235 | 4.20 m | 3.64 m | 2.97 m Douglas Fir – Larch[1] | No. 3 | 38 × 286 | 4.87 m | 4.22 m | 3.44 m Douglas Fir – Larch[1] | Construction | 38 × 89 | 2.51 m | 2.21 m | 1.80 m Douglas Fir – Larch[1] | Standard | 38 × 89 | 1.91 m | 1.65 m | 1.35 m Hem – Fir[2] | Select Structural | 38 × 89 | 2.67 m | 2.43 m | 2.12 m Hem – Fir[2] | Select Structural | 38 × 140 | 4.20 m | 3.82 m | 3.33 m Hem – Fir[2] | Select Structural | 38 × 184 | 5.52 m | 5.02 m | 4.38 m Hem – Fir[2] | Select Structural | 38 × 235 | 7.05 m | 6.41 m | 5.54 m Hem – Fir[2] | Select Structural | 38 × 286 | 8.58 m | 7.80 m | 6.42 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 89 | 2.59 m | 2.36 m | 2.06 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 140 | 4.08 m | 3.71 m | 3.08 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 184 | 5.31 m | 4.60 m | 3.75 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 235 | 6.49 m | 5.62 m | 4.59 m Hem – Fir[2] | No. 1 and No. 2 | 38 × 286 | 7.53 m | 6.52 m | 5.33 m Hem – Fir[2] | No. 3 | 38 × 89 | 2.44 m | 2.11 m | 1.72 m Hem – Fir[2] | No. 3 | 38 × 140 | 3.48 m | 3.01 m | 2.46 m Hem – Fir[2] | No. 3 | 38 × 184 | 4.23 m | 3.67 m | 2.99 m Hem – Fir[2] | No. 3 | 38 × 235 | 5.18 m | 4.48 m | 3.66 m Hem – Fir[2] | No. 3 | 38 × 286 | 6.01 m | 5.20 m | 4.25 m Hem – Fir[2] | Construction | 38 × 89 | 2.51 m | 2.28 m | 1.89 m Hem – Fir[2] | Standard | 38 × 89 | 2.00 m | 1.73 m | 1.41 m Spruce – Pine – Fir[3] | Select Structural | 38 × 89 | 2.55 m | 2.32 m | 2.03 m Spruce – Pine – Fir[3] | Select Structural | 38 × 140 | 4.02 m | 3.65 m | 3.19 m Spruce – Pine – Fir[3] | Select Structural | 38 × 184 | 5.28 m | 4.80 m | 4.19 m Spruce – Pine – Fir[3] | Select Structural | 38 × 235 | 6.74 m | 6.13 m | 5.35 m Spruce – Pine – Fir[3] | Select Structural | 38 × 286 | 8.21 m | 7.46 m | 6.52 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 89 | 2.47 m | 2.24 m | 1.96 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 140 | 3.89 m | 3.53 m | 3.08 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 184 | 5.11 m | 4.64 m | 3.89 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 235 | 6.52 m | 5.82 m | 4.75 m Spruce – Pine – Fir[3] | No. 1 and No. 2 | 38 × 286 | 7.80 m | 6.76 m | 5.52 m Spruce – Pine – Fir[3] | No. 3 | 38 × 89 | 2.43 m | 2.11 m | 1.72 m Spruce – Pine – Fir[3] | No. 3 | 38 × 140 | 3.48 m | 3.01 m | 2.46 m Spruce – Pine – Fir[3] | No. 3 | 38 × 184 | 4.23 m | 3.67 m | 2.99 m Spruce – Pine – Fir[3] | No. 3 | 38 × 235 | 5.18 m | 4.48 m | 3.66 m Spruce – Pine – Fir[3] | No. 3 | 38 × 286 | 6.01 m | 5.20 m | 4.25 m Spruce – Pine – Fir[3] | Construction | 38 × 89 | 2.43 m | 2.20 m | 1.93 m Spruce – Pine – Fir[3] | Standard | 38 × 89 | 2.07 m | 1.79 m | 1.47 m Northern Species[4] | Select Structural | 38 × 89 | 2.28 m | 2.07 m | 1.81 m Northern Species[4] | Select Structural | 38 × 140 | 3.59 m | 3.26 m | 2.85 m Northern Species[4] | Select Structural | 38 × 184 | 4.72 m | 4.29 m | 3.68 m Northern Species[4] | Select Structural | 38 × 235 | 6.03 m | 5.48 m | 4.51 m Northern Species[4] | Select Structural | 38 × 286 | 7.34 m | 6.40 m | 5.23 m Northern Species[4] | No. 1 and No. 2 | 38 × 89 | 2.23 m | 2.03 m | 1.77 m Northern Species[4] | No. 1 and No. 2 | 38 × 140 | 3.51 m | 3.14 m | 2.56 m Northern Species[4] | No. 1 and No. 2 | 38 × 184 | 4.41 m | 3.82 m | 3.12 m Northern Species[4] | No. 1 and No. 2 | 38 × 235 | 5.40 m | 4.67 m | 3.82 m Northern Species[4] | No. 1 and No. 2 | 38 × 286 | 6.26 m | 5.42 m | 4.43 m Northern Species[4] | No. 3 | 38 × 89 | 1.95 m | 1.69 m | 1.38 m Northern Species[4] | No. 3 | 38 × 140 | 2.79 m | 2.42 m | 1.97 m Northern Species[4] | No. 3 | 38 × 184 | 3.40 m | 2.94 m | 2.40 m Northern Species[4] | No. 3 | 38 × 235 | 4.15 m | 3.60 m | 2.94 m Northern Species[4] | No. 3 | 38 × 286 | 4.82 m | 4.17 m | 3.41 m Northern Species[4] | Construction | 38 × 89 | 2.18 m | 1.93 m | 1.57 m Northern Species[4] | Standard | 38 × 89 | 1.66 m | 1.44 m | 1.17 m Notes to Table 9.23.4.2.-F: (1) Includes Douglas Fir and Western Larch. (2) Includes Western Hemlock and Amabilis Fir. (3) Includes Spruce (all species except Coast Sitka Spruce), Jack Pine, Lodgepole Pine, Balsam Fir and Alpine Fir. (4) Includes any Canadian Species covered by the NLGA Standard Grading Rules.

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  • OBC Div. B 9.23.5.1. Holes Drilled in Framing Members

    (1)Holes drilled in roof, floor or ceiling framing members shall be not larger than one-quarter the depth of the member and shall be located not less than 50 mm from the edges, unless the depth of the member is increased by the size of the hole.

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  • OBC Div. B 9.23.5.2. Notching of Framing Members

    (1)Floor, roof and ceiling framing members are permitted to be notched provided the notch is located on the top of the member within half the joist depth from the edge of bearing and is not deeper than one-third the joist depth, unless the depth of the member is increased by the size of the notch.

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  • OBC Div. B 9.23.5.3. Wall Studs

    (1)Wall studs shall not be notched, drilled or otherwise damaged so that the undamaged portion of the stud is less than two-thirds the depth of the stud if the stud is loadbearing or 40 mm if the stud is non-loadbearing, unless the weakened studs are suitably reinforced.

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  • OBC Div. B 9.23.5.4. Top Plates

    (1)Top plates in walls shall not be notched, drilled or otherwise weakened to reduce the undamaged width to less than 50 mm unless the weakened plates are suitably reinforced.

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  • OBC Div. B 9.23.5.5. Roof Trusses

    (1)Roof truss members shall not be notched, drilled or otherwise weakened unless such notching or drilling is allowed for in the design of the truss.

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  • OBC Div. B 9.23.3.4. Nailing of Framing

    (1)Except as provided in Sentence (2), nailing of framing shall conform to Table 9.23.3.4.

    (2)Where the bottom wall plate or sole plate of an exterior wall is not nailed to joists or blocking in conformance with Table 9.23.3.4., the exterior wall is permitted to be fastened to the floor framing by

    (a)having plywood, OSB or waferboard sheathing extend down over floor framing and fastened to the floor framing by nails or staples conforming to Article 9.23.3.5., or

    (b)tying the wall framing to the floor framing by 50 mm wide galvanized-metal strips

    (i)50 mm wide.

    (ii)not less than 0.41 mm thick,

    (iii)spaced not more than 1.2 m apart, and

    (iv)fastened at each end with at least two 63 mm nails.

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  • OBC Div. B 9.23.6.1. Anchorage of Building Frames

    (1)Except as required by Sentence 9.23.6.3.(1), building frames shall be anchored to the foundation unless a structural analysis that considers wind and earthquake loads and lateral earth pressures shows that anchorage is not required

    (2)Except as provided in Sentences (3) to (6), anchorage shall be provided by

    (a)embedding the ends of the first floor joists in concrete, or

    (b)fastening the sill plate to the foundation with not less than 12.7 mm diam anchor bolts spaced not more than 2.4 m o.c.

    (3)For buildings with 2 or more floors supported by frame walls that are in areas where the seismic spectral acceleration, S_a(0.2) , is not greater than 0.70 or the 1-in-50 hourly wind pressure (HWP) is equal to or greater than 0.80 kPa but not greater than 1.20 kPa, anchorage shall be provided by fastening the sill plate to the foundation with not less than two anchor bolts per braced wall panel, where all anchor bolts used are

    (a)not less than 15.9 mm in diameter, located within 0.5 m of the end of the foundation, and spaced not more than 2.4 m o.c, or

    (b)not less than 12.7 mm in diameter, located within 0.5 m of the end of the foundation, and spaced not more than 1.7 m o.c.

    (4)For buildings supported by frame walls that are in areas where the seismic spectral acceleration, S_a(0.2) , is greater than 0.70 but not greater than 1.8 and the 1-in-50 hourly wind pressure (HWP) is not greater than 1.20 kPa, anchorage shall be provided by fastening the sill plate to the foundation with not less than two anchor bolts per braced wall panel located within 0.5 m of the end of the foundation and spaced in accordance with Table 9.23.6.1.

    (5)Anchor bolts referred to in Sentences (2) to (4) shall be

    (a)fastened to the sill plate with nuts and washers,

    (b)embedded not less than 100 mm in the foundation, and

    (c)so designed that they may be tightened without withdrawing them from the foundation.

    (6)Where the seismic spectral acceleration, S_a(0.2) , is greater than 1.8 or the 1-in-50 hourly wind pressure is equal to or greater than 1.2 kPa, anchorage shall be designed according to Part 4.

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  • OBC Div. B 9.23.6.2. Anchorage of Columns and Posts

    (1)Except as provided in Sentences (2) and (3), exterior columns and posts shall be anchored to resist uplift and lateral movement.

    (2)Except as provided in Sentence (3), where columns or posts support balconies, decks, verandas and other exterior platforms, and the distance from finished ground to the underside of the joists is not more than 600 mm,

    (a)the columns or posts shall be anchored to the foundation to resist uplift and lateral movement, or

    (b)the supported joists or beams shall be directly anchored to the ground to resist uplift.

    (3)Anchorage is not required for platforms described in Sentence (2) that

    (a)are not more than 1 storey in height,

    (b)are not more than 55 m² in area,

    (c)do not support a roof, and

    (d)are not attached to another structure, unless it can be demonstrated that differential movement will not adversely affect the performance of the structure to which the platform is attached.

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  • OBC Div. B 9.23.8.1. Bearing for Beams

    (1)Beams shall have even and level bearing and the bearing at end supports shall be not less than 89 mm long, except as stated in the notes to Span Tables 9.23.4.2.-H to 9.23.4.2.-K.

    .

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  • OBC Div. B 9.23.9.1. End Bearing for Joists

    (1)Except when supported on ribbon boards, floor joists shall have not less than 38 mm length of end bearing.

    (2)Ribbon boards referred to in Sentence (1) shall be not less than 19 mm by 89 mm lumber let into the studs.

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  • OBC Div. B 9.23.8.3. Built-up Wood Beams

    (1)Where a beam is made up of individual pieces of lumber that are nailed together, the individual members shall be 38 mm or greater in thickness and installed on edge.

    (2)Except as permitted in Sentence (3), where individual members of a built-up beam are butted together to form a joint, the joint shall occur over a support.

    (3)Where a beam is continuous over more than one span, individual members are permitted to be butted together to form a joint at or within 150 mm of the end quarter points of the clear spans, provided the quarter points are not those closest to the ends of the beam.

    (4)Members joined at quarter points shall be continuous over adjacent supports.

    (5)Joints in individual members of a beam that are located at or near the end quarter points shall not occur in adjacent members at the same quarter point and shall not reduce the effective beam width by more than half.

    (6)Not more than one butt joint shall occur in any individual member of a built-up beam within any one span.

    (7)Except as provided in Sentence (8), where 38 mm members are laid on edge to form a built-up beam, individual members shall be nailed together with a double row of nails not less than 89 mm in length, spaced not more than 450 mm apart in each row with the end nails located 100 mm to 150 mm from the end of each piece.

    (8)Where 38 mm members in built-up wood beams are not nailed together as provided in Sentence (7), they shall be bolted together with not less than 12.7 mm diam bolts equipped with washers and spaced not more than 1.2 m o.c., with the end bolts located not more than 600 mm from the ends of the members.

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  • OBC Div. B 9.23.9.9. Cantilevered Floor Joists

    (1)Floor joists supporting roof loads shall not be cantilevered more than 400 mm beyond their supports where 38 mm by 184 mm joists are used and not more than 600 mm beyond their supports where 38 mm by 235 mm or larger joists are used.

    (2)The cantilevered portions referred to in Sentence (1) shall not support floor loads from other storeys unless calculations are provided to show that the design resistances of the cantilevered joists are not exceeded.

    (3)Where cantilevered floor joists described in Sentences (1) and (2) are at right angles to the main floor joists, the tail joists in the cantilevered portion shall extend inward away from the cantilever support a distance equal to not less than 6 times the length of the cantilever, and shall be end nailed to an interior doubled header joist in conformance with Table 9.23.3.4.

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  • OBC Div. B 9.23.9.8. Support of Walls

    (1)Non-loadbearing walls parallel to the floor joists shall be supported by joists beneath the wall or on blocking between the joists.

    (2)Blocking referred to in Sentence (1) for the support of non-loadbearing walls shall be

    (a)not less than 38 mm by 89 mm lumber, and

    (b)except as required for the fastening of walls constructed with required braced wall panels, spaced not more than 1.2 m apart.

    (3)Except as provided in Sentence (6), non-loadbearing interior walls at right angles to the floor joists are not restricted as to location.

    (4)Loadbearing interior walls parallel to floor joists shall be supported by beams or walls of sufficient strength to safely transfer the design loads to the vertical supports.

    (5)Unless the joist size is designed to support such loads, loadbearing interior walls at right angles to floor joists shall be located

    (a)not more than 900 mm from the joist support where the wall does not support a floor, and

    (b)not more than 600 mm from the joist support where the wall supports one or more floors.

    (6)Loadbearing and non-loadbearing walls constructed with required braced wall panels shall be continuously supported by floor joists, blocking or rim joists to allow for the required fastening. (See Table 9.23.3.4.)

    Open OBC Div. B 9.23.9.8. in the code viewer
  • OBC Div. B Table 9.23.10.1. Size and Spacing of Studs — Forming Part of Sentence 9.23.10.1.(1)

    Table 9.23.10.1. Size and Spacing of Studs — Forming Part of Sentence 9.23.10.1.(1) Type of Wall | Supported Loads (including dead loads) | Minimum Stud Size, mm | Maximum Stud Spacing, mm | Maximum Unsupported Height, m Interior | No load | 38 × 38 | 400 | 2.4 Interior | No load | 38 × 89 flat[1] | 400 | 3.6 Interior | Attic not accessible by a stairway | 38 × 64 | 600 | 3.0 Interior | Attic not accessible by a stairway | 38 × 64 flat[1] | 400 | 2.4 Interior | Attic not accessible by a stairway | 38 × 89 | 600 | 3.6 Interior | Attic not accessible by a stairway | 38 × 89 flat[1] | 400 | 2.4 Interior | Attic accessible by a stairway plus one floorRoof load plus one floor Attic not accessible by stairway plus 2 floors | 38 × 89 | 400 | 3.6 Interior | Roof load, Attic accessible by a stairwayAttic not accessible by a stairway plus one floor | 38 × 64 | 400 | 2.4 Interior | Roof load, Attic accessible by a stairway Attic not accessible by a stairway plus one floor | 38 × 89 | 600 | 3.6 Interior | Attic accessible by a stairway plus 2 floors Roof load plus 2 floors | 38 × 89 | 300 | 3.6 Interior | Attic accessible by a stairway plus 2 floors Roof load plus 2 floors | 64 × 89 | 400 | 3.6 Interior | Attic accessible by a stairway plus 2 floors Roof load plus 2 floors | 38 × 140 | 400 | 4.2 Interior | Attic accessible by a stairway plus 3 floors Roof load plus 3 floors | 38 × 140 | 300 | 4.2 Exterior | Roof with or without attic storage | 38 × 64 | 400 | 2.4 Exterior | Roof with or without attic storage | 38 × 89 | 600 | 3.0 Exterior | Roof with or without attic storage plus one floor | 38 × 89 | 400 | 3.0 Exterior | Roof with or without attic storage plus one floor | 38 × 140 | 600 | 3.0 Exterior | Roof with or without attic storage plus 2 floors | 38 × 89 | 300 | 3.0 Exterior | Roof with or without attic storage plus 2 floors | 64 × 89 | 400 | 3.0 Exterior | Roof with or without attic storage plus 3 floors | 38 × 140 | 300 | 1.8 Notes to Table 9.23.10.1.: (1) See Article 9.23.10.3.

    Open OBC Div. B Table 9.23.10.1. in the code viewer
  • OBC Div. B 9.23.10.4. Continuity of Studs

    (1)Wall studs shall be continuous for the full storey height except at openings and shall not be spliced except by finger-jointing with a structural adhesive. (See Note A-9.23.10.4.(1))

    Open OBC Div. B 9.23.10.4. in the code viewer
  • OBC Div. B 9.23.10.6. Studs at Sides of Openings

    (1)Where the lintel spanning the opening is more than 3 m long, studs shall be tripled on each side of the opening so that

    (a)the two inner studs on each side extend from the bottom of the supported lintel to the top of the bottom wall plate, and

    (b)the outer stud on each side extends from the bottom of the top wall plate to the bottom wall plate.

    (2)Except as provided in Sentence (3), where the lintel spanning the opening is not more than 3 m long, studs shall be doubled on each side of the opening so that

    (a)the inner study on each side extend from the bottom of the supported lintel to the top of the bottom wall plate, and

    (b)the outer stud on each side extends from the bottom of the top wall plate to the bottom wall plate.

    (3)Single studs are permitted to be used on either side of openings

    (a)in non-loadbearing interior walls not required to have fire-resistance ratings, provided the studs extend from the top wall plate to the bottom wall plate, or

    (b)in loadbearing or non-loadbearing interior or exterior walls, provided

    (i)the opening is less than and within the required stud spacing, and

    (ii)no 2 such openings of full stud-space width are located in adjacent stud spaces.

    (See Note A-9.23.10.6.(3))

    Open OBC Div. B 9.23.10.6. in the code viewer
  • OBC Div. B 9.23.12.3. Lintel Spans and Sizes

    (1)Spans and sizes of wood lintels shall conform to the spans shown in Span Tables 9.23.4.2.-L and 9.23.12.3.-A to 9.23.12.3.-D

    (a)for buildings of residential occupancy,

    (b)where the wall studs exceed 38 mm by 64 mm in size,

    (c)where the spans of supported joists do not exceed 4.9 m, and

    (d)where the spans of trusses do not exceed 9.8 m.

    (2)In loadbearing exterior and interior walls of 38 mm by 64 mm framing members, lintels shall consist of

    (a)64 mm thick members on edge, or

    (b)38 mm thick and 19 mm thick members fastened together with a double row of nails not less than 63 mm long and spaced not more than 450 mm apart.

    (3)Lintels referred to in Sentence (2)

    (a)shall be not less than 50 mm greater in depth than those shown in Span Tables 9.23.4.2.-L and 9.23.12.3.-A to 9.23.12.3.-D for the maximum spans shown, and

    (b)shall not exceed 2.24 m in length.

    Open OBC Div. B 9.23.12.3. in the code viewer
  • OBC Div. B Table 9.23.12.3-C. Maximum Spans for Spruce — Pine — Fir Lintels — No. 1 or No. 2 Grade — Non-Structural Sheathing — Specified Snow Load 1.0 kPa

    Table 9.23.12.3.-C — Maximum Spans for Spruce — Pine — Fir Lintels — No. 1 or No. 2 Grade — Non-Structural Sheathing — Specified Snow Load 1.0 kPa Forming Part of Sentences 9.23.2.8.(1), 9.23.4.5.(1), 9.23.12.3.(1) and (3) Lintel Supporting | Lintel Size, mm | Exterior Walls, m | Interior Walls, m Limited attic storage and ceiling | 2 – 38 × 89 | N/A | 1.27 Limited attic storage and ceiling | 2 – 38 × 140 | N/A | 1.93 Limited attic storage and ceiling | 2 – 38 × 184 | N/A | 2.35 Limited attic storage and ceiling | 2 – 38 × 235 | N/A | 2.88 Limited attic storage and ceiling | 2 – 38 × 286 | N/A | 3.34 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 89 | 2.55 | 1.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 140 | 4.01 | 2.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 184 | 5.27 | 3.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 235 | 6.37 | 4.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 286 | 7.38 | 5.87 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 89 | 1.27 | 0.93 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 140 | 1.93 | 1.35 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 184 | 2.35 | 1.64 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 235 | 2.88 | 2.01 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 286 | 3.34 | 2.33 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 89 | 1.05 | 0.74 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 140 | 1.49 | 1.02 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 184 | 1.82 | 1.20 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 235 | 2.22 | 1.45 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 286 | 2.58 | 1.66 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 89 | 0.94 | 0.64 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 140 | 1.34 | 0.88 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 184 | 1.63 | 1.05 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 235 | 1.99 | 1.27 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 286 | 2.31 | 1.45 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 89 | 0.88 | 0.59 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 140 | 1.25 | 0.81 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 184 | 1.52 | 0.97 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 235 | 1.86 | 1.17 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 286 | 2.11 | 1.35 Table 9.23.12.3.-C (continued) — Maximum Spans for Spruce — Pine — Fir Lintels — No. 1 or No. 2 Grade — Non-Structural Sheathing — Specified Snow Load 1.5 kPa Lintel Supporting | Lintel Size, mm | Exterior Walls, m | Interior Walls, m Limited attic storage and ceiling | 2 – 38 × 89 | N/A | 1.27 Limited attic storage and ceiling | 2 – 38 × 140 | N/A | 1.93 Limited attic storage and ceiling | 2 – 38 × 184 | N/A | 2.35 Limited attic storage and ceiling | 2 – 38 × 235 | N/A | 2.88 Limited attic storage and ceiling | 2 – 38 × 286 | N/A | 3.34 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 89 | 2.23 | 1.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 140 | 3.50 | 2.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 184 | 4.61 | 3.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 235 | 5.76 | 4.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 286 | 6.67 | 5.87 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 89 | 1.11 | 0.93 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 140 | 1.66 | 1.35 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 184 | 2.02 | 1.64 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 235 | 2.47 | 2.01 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 286 | 2.87 | 2.33 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 89 | 0.96 | 0.74 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 140 | 1.37 | 1.02 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 184 | 1.67 | 1.20 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 235 | 2.04 | 1.45 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 286 | 2.36 | 1.66 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 89 | 0.88 | 0.64 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 140 | 1.26 | 0.88 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 184 | 1.53 | 1.05 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 235 | 1.87 | 1.27 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 286 | 2.12 | 1.45 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 89 | 0.83 | 0.59 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 140 | 1.19 | 0.81 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 184 | 1.44 | 0.97 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 235 | 1.73 | 1.17 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 286 | 1.96 | 1.35 Table 9.23.12.3.-C (continued) — Maximum Spans for Spruce — Pine — Fir Lintels — No. 1 or No. 2 Grade — Non-Structural Sheathing — Specified Snow Load 2.0 kPa Lintel Supporting | Lintel Size, mm | Exterior Walls, m | Interior Walls, m Limited attic storage and ceiling | 2 – 38 × 89 | N/A | 1.27 Limited attic storage and ceiling | 2 – 38 × 140 | N/A | 1.93 Limited attic storage and ceiling | 2 – 38 × 184 | N/A | 2.35 Limited attic storage and ceiling | 2 – 38 × 235 | N/A | 2.88 Limited attic storage and ceiling | 2 – 38 × 286 | N/A | 3.34 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 89 | 2.02 | 1.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 140 | 3.18 | 2.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 184 | 4.18 | 3.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 235 | 5.34 | 4.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 286 | 6.21 | 5.87 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 89 | 1.01 | 0.93 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 140 | 1.48 | 1.35 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 184 | 1.80 | 1.64 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 235 | 2.20 | 2.01 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 286 | 2.56 | 2.33 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 89 | 0.89 | 0.74 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 140 | 1.27 | 1.02 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 184 | 1.55 | 1.20 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 235 | 1.89 | 1.45 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 286 | 2.15 | 1.66 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 89 | 0.83 | 0.64 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 140 | 1.19 | 0.88 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 184 | 1.44 | 1.05 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 235 | 1.72 | 1.27 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 286 | 1.96 | 1.45 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 89 | 0.80 | 0.59 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 140 | 1.14 | 0.81 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 184 | 1.35 | 0.97 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 235 | 1.62 | 1.17 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 286 | 1.84 | 1.35 Table 9.23.12.3.-C (continued) — Maximum Spans for Spruce — Pine — Fir Lintels — No. 1 or No. 2 Grade — Non-Structural Sheathing — Specified Snow Load 2.5 kPa Lintel Supporting | Lintel Size, mm | Exterior Walls, m | Interior Walls, m Limited attic storage and ceiling | 2 – 38 × 89 | N/A | 1.27 Limited attic storage and ceiling | 2 – 38 × 140 | N/A | 1.93 Limited attic storage and ceiling | 2 – 38 × 184 | N/A | 2.35 Limited attic storage and ceiling | 2 – 38 × 235 | N/A | 2.88 Limited attic storage and ceiling | 2 – 38 × 286 | N/A | 3.34 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 89 | 1.88 | 1.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 140 | 2.96 | 2.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 184 | 3.88 | 3.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 235 | 4.96 | 4.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 286 | 5.87 | 5.87 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 89 | 0.93 | 0.93 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 140 | 1.35 | 1.35 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 184 | 1.64 | 1.64 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 235 | 2.01 | 2.01 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 286 | 2.33 | 2.33 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 89 | 0.84 | 0.74 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 140 | 1.19 | 1.02 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 184 | 1.44 | 1.20 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 235 | 1.73 | 1.45 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 286 | 1.96 | 1.66 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 89 | 0.79 | 0.64 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 140 | 1.13 | 0.88 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 184 | 1.33 | 1.05 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 235 | 1.60 | 1.27 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 286 | 1.82 | 1.45 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 89 | 0.77 | 0.59 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 140 | 1.08 | 0.81 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 184 | 1.27 | 0.97 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 235 | 1.53 | 1.17 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 286 | 1.74 | 1.35 Table 9.23.12.3.-C (continued) — Maximum Spans for Spruce — Pine — Fir Lintels — No. 1 or No. 2 Grade — Non-Structural Sheathing — Specified Snow Load 3.0 kPa Lintel Supporting | Lintel Size, mm | Exterior Walls, m | Interior Walls, m Limited attic storage and ceiling | 2 – 38 × 89 | N/A | 1.27 Limited attic storage and ceiling | 2 – 38 × 140 | N/A | 1.93 Limited attic storage and ceiling | 2 – 38 × 184 | N/A | 2.35 Limited attic storage and ceiling | 2 – 38 × 235 | N/A | 2.88 Limited attic storage and ceiling | 2 – 38 × 286 | N/A | 3.34 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 89 | 1.77 | 1.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 140 | 2.78 | 2.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 184 | 3.66 | 3.88 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 235 | 4.67 | 4.96 Roof and ceiling only (tributary width of 0.6 m maximum)[5] | 2 – 38 × 286 | 5.61 | 5.87 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 89 | 0.87 | 0.93 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 140 | 1.25 | 1.35 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 184 | 1.52 | 1.64 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 235 | 1.84 | 2.01 Roof and ceiling only (tributary width of 4.9 m maximum)[6] | 2 – 38 × 286 | 2.09 | 2.33 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 89 | 0.79 | 0.74 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 140 | 1.13 | 1.02 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 184 | 1.33 | 1.20 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 235 | 1.59 | 1.45 Roof, ceiling and 1 storey[3][6][7] | 2 – 38 × 286 | 1.81 | 1.66 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 89 | 0.76 | 0.64 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 140 | 1.06 | 0.88 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 184 | 1.25 | 1.05 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 235 | 1.50 | 1.27 Roof, ceiling and 2 storeys[3][6][7] | 2 – 38 × 286 | 1.71 | 1.45 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 89 | 0.74 | 0.59 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 140 | 1.02 | 0.81 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 184 | 1.21 | 0.97 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 235 | 1.45 | 1.17 Roof, ceiling and 3 storeys[3][6][7] | 2 – 38 × 286 | 1.66 | 1.35 Notes to Table 9.23.12.3.-C: (1) Where structural sheathing is used, lintel spans may be increased by 15%. Structural sheathing consists of a minimum 9.5 mm thick structural panel conforming to CSA O121, CSA O151, CSA O325 or CSA O437.0 fastened with at least two rows of fasteners to the exterior face of the lintel, and a single row to the top plates and studs. Fasteners shall conform to Table 9.23.3.5.-A. (2) A single piece of 89 mm thick lumber may be used in lieu of 2 pieces of 38 mm thick lumber on edge. (3) If floor joists span the full width of the building without support, lintel spans shall be reduced by 15% for “Roof, ceiling and 1 storey”, by 20% for “Roof, ceiling and 2 storeys”, and by 25% for “Roof, ceiling and 3 storeys”. (4) For ends of lintels fully supported by walls, provide minimum bearing length of 38 mm for lintel spans up to 3 m, or minimum bearing length of 76 mm for lintel spans greater than 3 m. (5) Spans for 0.6 m tributary width are calculated for lintels in end walls that support only a 0.6 m width of roof and ceiling, but do not support roof joists, roof rafters or roof trusses. (6) Lintel spans are calculated based on a maximum floor joist, roof joist or rafter span of 4.9 m and a maximum roof truss span of 9.8 m. Lintel spans may be increased by 5% if rafter and joist spans are not more than 4.3 m and roof truss spans are not more than 8.6 m. Spans may be increased by 10% if rafter and joist spans are not more than 3.7 m and roof trusses are not more than 7.4 m. (7) Spans apply only where the floors serve residential areas as described in Table 4.1.5.3., or the uniformly distributed live load does not exceed that specified for residential areas as described in Table 4.1.5.3.

    Open OBC Div. B Table 9.23.12.3-C. in the code viewer
  • OBC Div. B 9.23.13.1. Requirements for Low to Moderate Wind and Seismic Forces

    (1)This Article applies in locations where the seismic spectral acceleration, S_a(0.2) , is not more than 0.70 and the 1-in-50 hourly wind pressure is less than 0.80 kPa.

    (2)Bracing to resist lateral loads shall be designed and constructed as follows:

    (a)exterior walls shall be

    (i)clad with panel-type cladding in accordance with Section 9.27.,

    (ii)sheathed with plywood, OSB, waferboard, fibreboard, gypsum board or diagonal lumber sheathing complying with Subsection 9.23.17. and fastened in accordance with Table 9.23.3.5.-A, or

    (iii)finished on the interior with a panel-type material in accordance with the requirements of Section 9.29., or

    (b)in accordance with

    (i)Articles 9.23.13.4. to 9.23.13.7.,

    (ii)Part 4, or

    (iii)good engineering practice such as that provided in CWC 2014, "Engineering Guide for Wood Frame Construction."

    Open OBC Div. B 9.23.13.1. in the code viewer
  • OBC Div. B 9.23.13.4. Braced Wall Bands

    (1)Braced wall bands shall

    (a)be full storey height,

    (b)be not more than 1.2 m wide,

    (c)lap at both ends with another braced wall band,

    (d)be aligned with braced wall bands on storeys above and below, and

    (e)conform to the spacing and dimensions given in Table 9.23.13.5.

    (2)The perimeter of the building shall be located within braced wall bands.

    (3)For split-level buildings, a braced wall band shall be located where there is a change in floor level greater than the depth of one floor joist.

    Open OBC Div. B 9.23.13.4. in the code viewer
  • OBC Div. B 9.23.14.8. Ridge Support

    (1)Except as provided in Sentence (4), roof rafters and joists shall be supported at the ridge of the roof by

    (a)a loadbearing wall extending from the ridge to suitable bearing, or

    (b)a ridge beam supported by not less than 89 mm length of bearing.

    (2)Except as provided in Sentence (3), the ridge beam referred to in Sentence (1) shall conform to the sizes and spans shown in Span Table 9.23.4.2.-L, provided

    (a)the supported rafter or joist length does not exceed 4.9 m, and

    (b)the roof does not support any concentrated loads.

    (3)The ridge beam referred to in Sentence (1) need not comply with Sentence (2) where

    (a)the beam is of not less than 38 mm by 140 mm material, and

    (b)the beam is supported at intervals not exceeding 1.2 m by not less than 38 mm by 89 mm members extending vertically from the ridge to suitable bearing.

    (4)When the roof slope is 1 in 3 or steeper, ridge support need not be provided when the lower ends of the rafters are adequately tied to prevent outward movement.

    (5)Ties required in Sentence (4) are permitted to consist of tie rods or ceiling joists forming a continuous tie for opposing rafters and nailed in accordance with Table 9.23.14.8.

    (6)Except as permitted in Sentence (7), ceiling joists referred to in Sentence (5) shall be tied to the base of every rafter.

    (7)Where ceiling joists referred to in Sentence (5) are raised above the base of the rafters, the connections between the rafters and the ceiling joists shall be designed in accordance with Clause 9.4.1.1.(1)(b) or (c).

    (8)Ceiling joists referred to in Sentence (5) that are spliced to make a continuous joist shall be fastened together at each splice with at least one more nail than required for the rafter-to-joist connection shown in Table 9.23.14.8.

    (9)Members referred to in Sentences (6) and (8) are permitted to be fastened together either directly or through a gusset plate.

    Open OBC Div. B 9.23.14.8. in the code viewer
  • OBC Div. B 9.23.15.5. Subfloor Thickness or Rating

    (1)Except as provided in Sentences (2) and (3), subfloors shall conform to Table 9.23.15.5.-A or 9.23.15.5.-B.

    (2)Where the finished flooring consists of not less than 19 mm matched wood strip flooring laid at right angles to joists spaced not more than 600 mm o.c., subflooring shall be permitted to consist of not less than

    (a)12.5 mm thick plywood,

    (b)12.5 mm thick OSB conforming to O-2 grade,

    (c)12.7 mm thick OSB conforming to O-1 grade,

    (d)12.7 mm thick waferboard conforming to R-1 grade, or

    (e)OSB conforming to 2R32 / 2F16 grade.

    (3)Except where the flooring consists of ceramic tiles applied with adhesive, where a separate panel-type underlay or concrete topping is applied to a subfloor on joists spaced not more than 400 mm o.c., the subfloor is permitted to consist of not less than

    (a)12.5 mm thick plywood,

    (b)12.5 mm thick OSB conforming to O-2 grade,

    (c)12.7 mm thick OSB conforming to O-1 grade,

    (d)12.7 mm thick waferboard conforming to R-1 grade, or

    (e)OSB conforming to 2R32 / 2F16 grade.

    Open OBC Div. B 9.23.15.5. in the code viewer
  • OBC Div. B 9.23.16.7. Thickness or Rating

    (1)The thickness or rating of roof sheathing on a flat roof used as a walking deck shall conform to either Table 9.23.15.5.-A or 9.23.15.5.-B for subfloors.

    (2)The thickness or rating of roof sheathing on a roof not used as a walking deck shall conform to either Table 9.23.16.7.-A or Table 9.23.16.7.-B.

    (3)Asphalt-coated or asphalt-impregnated fibreboard not less than 11.1 mm thick conforming to CAN/ULC-S706.1, "Standard for Wood Fibre Insulating Boards for Buildings," is permitted to be used as a roof sheathing over supports spaced not more than 400 mm o.c., provided the roofing consists of

    (a)a continuous sheet of galvanized steel not less than 0.33 mm in thickness, or

    (b)a continuous sheet of aluminum not less than 0.61 mm in thickness.

    (4)All edges of sheathing described in Sentence (3) shall be supported by blocking or framing.

    Open OBC Div. B 9.23.16.7. in the code viewer
  • OBC Div. B 9.24.1.1. Application

    (1)This Section applies to sheet steel study for use in non-loadbearing exterior and interior walls.

    (2)Where loadbearing steel studs are used, they shall be designed in conformance with Part 4.

    Open OBC Div. B 9.24.1.1. in the code viewer
  • OBC Div. B 9.24.3.1. Installation of Runners

    (1)Runners shall be provided at the tops and bottoms of walls.

    (2)Runners required in Sentence (1) shall be securely attached to the building at approximately 50 mm from the ends, and at intervals of not more than 600 mm o.c. for interior walls and 300 mm o.c. for exterior walls.

    (3)Fasteners used for attachment described in Sentence (2) shall consist of the equivalent of 63 mm nails or 25 mm screws.

    (4)Studs at openings and which are not full wall height shall be supported by a runner at the ends of the studs, securely fastened to the full length studs at the sides of the opening.

    Open OBC Div. B 9.24.3.1. in the code viewer
  • OBC Div. B 9.24.3.2. Fire-Rated Walls

    (1)Steel studs used in walls required to have a fire-resistance rating shall be installed so that there is not less than a 12 mm clearance between the top of the stud and the top of the runner to allow for expansion in the event of fire.

    (2)Except as provided in Article 9.24.3.6., studs in walls referred to in Sentence (1) shall not be attached to the runners in a manner that will prevent such expansion.

    (3)Framing above doors with steel door frames in non-loadbearing fire separations required to have a fire-resistance rating shall consist of 2 runners on the flat fastened back to back. (See Note A-9.24.3.2.(3))

    (4)The lower runner required in Sentence (3) shall be cut through the flanges and be bent at each end to extend upwards at least 150 mm and fastened to the adjacent studs.

    Open OBC Div. B 9.24.3.2. in the code viewer