Plumbing and Part 9 items used in large buildings (Large Buildings)

Last updated October 22, 2026

Values this chapter turns on

max shower and bathtub water temperature, general: 49°C; max shower and bathtub water temperature, general
max shower and bath temperature, healthcare: 43°C; max shower and bath temperature, healthcare
ceiling height over most living areas and kitchens: 2,300 mm; ceiling height over most living areas and kitchens
curb height with garage floor and ramp guards: 140 mm; curb height with garage floor and ramp guards

Part 3 buildings borrow more of Part 9 than many candidates expect. Article 3.7.1.1. sends room heights in dwelling units to Subsection 9.5.3., Article 3.7.1.2. sends dwelling unit room areas to Part 9, and Article 3.7.2.1. sends window areas for sleeping rooms and principal rooms to Part 9. The Large Buildings syllabus also lists Part 7 items on plumbing facilities and water temperature, plus Part 9 stairs, guards, cladding, finishes, ducts and lighting outlets. This chapter is a map of those borrowed rules. Note the exclusions: 9.5.2. (barrier-free in Part 9), 9.5.4. (hallways) and 9.5.5.1. and 9.5.5.2. (door sizes) are not on this exam.

Plumbing facilities and water temperature (Part 7)

Plumbing facilities are provided under Subsection 3.7.4. and Section 9.31. (7.1.1B.1.). A floor drain is required in a basement forming part of a dwelling unit where gravity drainage is possible, and in any public laundry room, garbage room, incinerator room or boiler or heating room outside a dwelling unit (7.1.1B.2.). Fixtures may not be placed in rooms that are not lit and ventilated to Parts 3, 6 and 9, and every fixture, valve and cleanout must be accessible (7.1.3.1., 7.1.3.2.).

Water temperature limits are a favourite question:

Situation	Maximum	Source
Shower heads and bathtubs, general	49°C	7.2.10.7.
Healthcare facilities and retirement homes	43°C, set at the fixture controls	7.2.10.7.
Fixtures used by patients or residents in Group B2/B3, group homes, child care	43°C, controls for staff only	7.2.10.7A.
Shower valve outlet or high-limit stop	49°C	7.2.10.7B.

Showers and tubs are normally controlled by an automatic compensating valve, and fixed shower heads need individual pressure-balanced or thermostatic-mixing valves unless supplied by a single tempered water line from an automatic compensating valve.

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Rooms, glass and windows (9.5, 9.6, 9.7)

For dwelling units, room heights come from Table 9.5.3.1.: 2,300 mm over most of living areas and kitchens, 2,300 mm over half a bedroom (or 2,100 mm over all of it), and 2,100 mm in halls and bathrooms where a person stands. Mezzanines in all occupancies need 2.1 m above and below (9.5.3.2.), and storage garages need 2 m clear (9.5.3.3.).

Room areas worth knowing:

Room	Minimum area
Living area	13.5 m² (11 m² when combined with kitchen and dining in a unit for up to 2 persons)
Kitchen	4.2 m² (3.7 m² in a unit for up to 2 persons)
One bedroom per unit	9.8 m² without built-ins, 8.8 m² with
Other bedrooms	7 m² without built-ins, 6 m² with
Bachelor unit, all spaces combined	13.5 m²

Sources: 9.5.3A.1., 9.5.3C.1., 9.5.3D.1., 9.5.3D.2., 9.5.3E.1.. Sleeping rooms outside dwelling units need 7 m² per person single and 4.6 m² per person shared (9.5.3D.4.).

Window areas come from Table 9.7.2.3. through 3.7.2.1.: living and dining rooms 10% of floor area, bedrooms 5%, and kitchens 10% only where there is no electric lighting. Article 3.7.2.1. switches off 9.9.10.1. (the egress window rule) for Part 3 buildings and adds its own rules for long-term care homes.

Glass in public areas: sidelights over 500 mm wide that could be mistaken for doors, and glass in sliding doors, must be safety glass or wired glass; other glass in doors needs it where the pane exceeds 0.5 m² and comes within 900 mm of the bottom of the door (9.6.1.4.). Dwelling unit entrance doors and ground floor windows also have forced-entry rules: wood doors at least 45 mm thick, deadbolts with 25 mm throw, and windows within 2 m of the ground meeting the forced-entry clause of the fenestration standard (9.7.5.2., 9.7.5.3.).

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Stairs, ramps, handrails and guards (9.8)

Section 9.8. is long; for Large Buildings, focus on values for stairs other than within a dwelling unit:

Item	Value	Source
Public stair rise	125 mm to 180 mm	Table 9.8.4.1.
Public stair run	280 mm minimum	Table 9.8.4.1.
Maximum height of one flight	3.7 m	9.8.3.3.
Clear height over stairs	2,050 mm	9.8.2.2.
Ramp slope: exterior / residential interior / industrial / other	1 in 10 / 1 in 10 / 1 in 6 / 1 in 8	9.8.5.4.
Handrail height	865 mm to 1,070 mm	9.8.7.4.
Guard height, general	1,070 mm	9.8.8.3.
Guard height, exterior stairs and landings over 10 m above ground	1,500 mm	9.8.8.3.
Guard openings	Stop a 100 mm sphere (535 mm rails allowed in industrial)	9.8.8.5.

Guards are needed where the drop exceeds 600 mm within 1.2 m, except at loading docks, repair garage pits and maintenance-only access (9.8.8.1.). In garages, a floor or ramp perimeter 600 mm or more above the next level needs both a 140 mm curb and a 1,070 mm guard (9.8.8.4.). Stairs and ramps outside dwelling units need slip-resistant finishes and contrasting leading edges, and those stairs also need a tactile attention indicator at the top (9.8.9.6.), and are designed for 4.8 kPa (9.8.9.1.).

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Cladding and interior finishes (9.27, 9.29)

Cladding questions are table reads: plywood cladding at least 6 mm over sheathing (9.27.8.2.); lumber siding at least 14.3 mm thick and not over 286 mm wide (9.27.6.2.); vinyl siding to ASTM D3679, with any required flame-spread rating found by CAN/ULC-S102.2 (9.27.12.1.).

For gypsum board, read Table 9.29.5.3. for support spacing and Table 9.29.5.5. for fastener penetration. Penetration increases with the fire-resistance rating for ceilings only: 15 mm screws or 20 mm nails with no rating, then 30 mm, 45 mm and 60 mm for 45 min, 1 h and 1.5 h ceilings. Screws on ceilings are spaced not over 300 mm (9.29.5.9.), and board supporting insulation is at least 12.7 mm thick (9.29.5.4.).

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Ducts, carbon monoxide alarms and lighting outlets

Ducts are noncombustible unless they meet Class 1 duct material rules, serve no more than 2 storeys vertically and carry air no hotter than 120°C; duct sealants are limited to a flame-spread rating of 25 and smoke developed classification of 50 (9.33.6.2.). Foamed plastic insulation on ducts is restricted (9.33.6.4.), and radiator surfaces may not exceed 70°C unless contact is prevented (9.33.7.2.).

The Part 9 carbon monoxide alarm Articles (9.32.3.9. to 9.32.3.9C.) mirror the Part 6 rules: suite alarms next to sleeping rooms and on each storey, corridor alarms not more than 25 m apart where the corridor is heated directly by forced air, and an alarm in every service room (outside a residential suite) that holds a fuel-burning appliance for building services or laundry drying.

Lighting outlets (9.34.2.1. to 9.34.2.7.): every entrance to a residential building gets an exterior light (switch may be restricted to staff for multi-suite entrances and hotels), unfinished basements get one outlet per 30 m², and public areas meet the illumination values in Table 9.34.2.7., such as 100 lx in public water closet rooms and 200 lx in service rooms and laundry areas.

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Common traps

Applying the 49°C limit in a retirement home (it is 43°C).
Applying 5% glass to living rooms.
Using the residential 1 in 10 ramp slope for an office.
Using the wall fastener value where the question is about a rated ceiling.

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.

Chapter at a glance: the key idea in each section
Section	Key idea
Plumbing facilities and water temperature (Part 7)	Plumbing facilities are provided under Subsection 3.7.4. and Section 9.31.. A floor drain is required in a basement forming part of a dwelling unit where gravity drainage is…
Rooms, glass and windows (9.5, 9.6, 9.7)	For dwelling units, room heights come from: 2,300 mm over most of living areas and kitchens, 2,300 mm over half a bedroom (or 2,100 mm over all of it), and 2,100 mm in halls and…
Stairs, ramps, handrails and guards (9.8)	Guards are needed where the drop exceeds 600 mm within 1.2 m, except at loading docks, repair garage pits and maintenance-only access.
Cladding and interior finishes (9.27, 9.29)	Cladding questions are table reads: plywood cladding at least 6 mm over sheathing; lumber siding at least 14.3 mm thick and not over 286 mm wide; vinyl siding to ASTM D3679, with…
Ducts, carbon monoxide alarms and lighting outlets	Ducts are noncombustible unless they meet Class 1 duct material rules, serve no more than 2 storeys vertically and carry air no hotter than 120°C; duct sealants are limited to a…

Plumbing facilities and water temperature (Part 7)
Plumbing facilities are provided under Subsection 3.7.4. and Section 9.31.. A floor drain is required in a basement forming part of a dwelling unit where gravity drainage is…
Rooms, glass and windows (9.5, 9.6, 9.7)
For dwelling units, room heights come from: 2,300 mm over most of living areas and kitchens, 2,300 mm over half a bedroom (or 2,100 mm over all of it), and 2,100 mm in halls and…
Stairs, ramps, handrails and guards (9.8)
Guards are needed where the drop exceeds 600 mm within 1.2 m, except at loading docks, repair garage pits and maintenance-only access.
Cladding and interior finishes (9.27, 9.29)
Cladding questions are table reads: plywood cladding at least 6 mm over sheathing; lumber siding at least 14.3 mm thick and not over 286 mm wide; vinyl siding to ASTM D3679, with…
Ducts, carbon monoxide alarms and lighting outlets
Ducts are noncombustible unless they meet Class 1 duct material rules, serve no more than 2 storeys vertically and carry air no hotter than 120°C; duct sealants are limited to a…

Usual exam traps

Applying the 49°C limit in a retirement home (it is 43°C).
Applying 5% glass to living rooms.
Using the residential 1 in 10 ramp slope for an office.
Using the wall fastener value where the question is about a rated ceiling.

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Questions on Plumbing and Part 9 items used in large buildings, 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.

OBC Div. B 7.1.1B.1. Facilities Required
(1)Plumbing facilities shall be provided in accordance with Subsection 3.7.4. and Section 9.31.
Open OBC Div. B 7.1.1B.1. in the code viewer
OBC Div. B 7.1.1B.2. Floor Drains
(1)Where gravity drainage to a sanitary drainage system is possible, a floor drain shall be installed in a basement forming part of a dwelling unit.
(2)Where gravity drainage to a sanitary drainage system is not possible, the floor drain required by Sentence (1) may be connected to a storm drainage system, dry well or drainage ditch provided it is located where it can receive only clear-water waste or storm sewage.
(3)A floor drain shall be provided in a public laundry room, garbage room, incinerator room, boiler or heating room that is not located within a dwelling unit.
Open OBC Div. B 7.1.1B.2. in the code viewer
OBC Div. B 7.1.3.1. Lighting and Ventilation Requirements
(1)Plumbing fixtures shall not be installed in a room that is not lighted and ventilated in accordance with the appropriate requirements in Parts 3, 6 and 9.
Open OBC Div. B 7.1.3.1. in the code viewer
OBC Div. B 7.1.3.2. Accessibility
(1)Every fixture, plumbing appliance, interceptor, cleanout, valve, device or piece of equipment shall be located so that it is readily accessible for use, cleaning and maintenance.
Open OBC Div. B 7.1.3.2. in the code viewer
OBC Div. B 7.2.10.7. Water Temperature Control
(1)Except as provided in Sentences (2) and (3), water supplied to shower heads or bathtubs shall be controlled by an automatic compensating valve conforming to
(a)ASME A112.18.1 / CSA B125.1, "Plumbing Supply Fittings," or
(b)ASSE 1016 / ASME A112.1016 / CSA B125.16, "Performance Requirements for Automatic Compensating Valves for Individual Showers and Tub/Shower Combinations."
(2)The requirement in Sentence (1) is permitted to be waived where hot water supplied only to bathtubs is controlled by
(a)an automatic compensating valve conforming to CSA B125.3, "Plumbing fittings," or
(b)a temperature-limiting device conforming to ASSE 1070 / ASME A112.1070 / CSA B125.70, "Performance requirements for water temperature limiting devices."
(3)The requirement in Sentence (1) is permitted to be waived where the water is supplied by a single tempered water line controlled by an automatic compensating valve conforming to CSA B125.3, "Plumbing fittings."
(4)Except as provided in Sentences (5) and (6) and 7.2.10.7A.(1), the temperature of water discharging from a shower head or into a bathtub shall not exceed 49°C.
(5)In healthcare facilities and retirement homes, the temperature of water discharging from a shower head or into a bathtub shall
(a)not exceed 43°C, and
(b)be adjusted at the shower or bathtub controls.
(6)Sentence (4) does not apply to hot water supplied to installed dishwashers or clothes washers.
Open OBC Div. B 7.2.10.7. in the code viewer
OBC Div. B 7.2.10.7A. Temperature Control Devices
(1)A water distribution system supplying hot water to any bathtub, shower or hand basin that is accessible to a patient or resident in a Group B, Division 2 or 3 occupancy or a resident of a group home, home for special care or residence for adults with developmental disabilities, or children within child care facilities shall have one or more temperature gauges and control devices that are
(a)accessible only to supervisory staff, and
(b)capable of being adjusted to ensure that the temperature of the water supplied to the fixtures does not exceed 43°C.
Open OBC Div. B 7.2.10.7A. in the code viewer
OBC Div. B 7.2.10.7B. Showers
(1)Except as provided for in Sentences (2) and (3), all valves supplying fixed location shower heads, shall be individually pressure-balanced or thermostatic-mixing valves, conforming to ASME A112.18.1 / CSA B125.1, "Plumbing Supply Fittings."
(2)An individually pressure-balanced or thermostatic-mixing valve is not required for shower heads having a single tempered water supply that is controlled by an automatic compensating valve conforming to CSA B125.3, "Plumbing fittings."
(3)Deck-mounted, hand-held, flexible-hose spray attachments are exempt from the thermal shock requirements of Sentences (1) and (4).
(4)Pressure-balanced, thermostatic-mixing or combination pressure-balanced and thermostatic-mixing type valves shall
(a)capable of limiting thermal shock, and
(b)designed so that the outlet temperature does not exceed 49°C or equipped with high-limit stops which shall be adjusted to a maximum hot water setting of 49°C.
Open OBC Div. B 7.2.10.7B. in the code viewer
OBC Div. B Table 9.5.3.1. Room Ceiling Heights — Forming Part of Sentences 9.5.3.1.(1) and (4)
Table 9.5.3.1 — Room Ceiling Heights — Forming Part of Sentences 9.5.3.1.(1) and (4) Room or Space | Minimum Heights[1] Living room or space, dining room or space, kitchen or kitchen space | 2,300 mm over at least 75% of the required floor area with a clear height of 2,100 mm at any point over the required area Bedroom or bedroom space | 2,300 mm over at least 50% of the required area or 2,100 mm over all of the required floor area. Any part of the floor having a clear height of less than 1,400 mm shall not be considered in computing the required floor area Basement space | 2,100 mm over at least 75% of the basement area except that under beams and ducts the clearance is permitted to be reduced to 1,950 mm Bathroom, water closet room or laundry area above grade | 2,100 mm in any area where a person would normally be in a standing position Passage, hall or main entrance vestibule and finished rooms not specifically mentioned above | 2,100 mm Notes to Table 9.5.3.1.: (1) Area of the space shall be measured at floor level.
Open OBC Div. B Table 9.5.3.1. in the code viewer

Show all 47 articles

OBC Div. B 9.5.3.2. Mezzanines
(1)The ceiling height above and below a mezzanine floor assembly in all occupancies shall be not less than 2.1 m.
Open OBC Div. B 9.5.3.2. in the code viewer
OBC Div. B 9.5.3.3. Storage Garages
(1)The clear height in a storage garage shall be not less than 2 m.
Open OBC Div. B 9.5.3.3. in the code viewer
OBC Div. B 9.5.3A.1. Areas of Living Rooms and Spaces
(1)Living areas within dwelling units, either as separate rooms or in combination with other spaces, shall have an area not less than 13.5 m².
(2)Where the area of a living space is combined with a kitchen and dining area, the living area alone in a dwelling unit that contains sleeping accommodation for not more than two persons shall be not less than 11 m².
Open OBC Div. B 9.5.3A.1. in the code viewer
OBC Div. B 9.5.3C.1. Kitchen Areas
(1)Kitchen areas within dwelling units either separate from or in combination with other spaces, shall have an area of not less than 4.2 m² including the area occupied by the base cabinets, except that in dwelling units containing sleeping accommodation for not more than two persons, the minimum area shall be 3.7 m².
Open OBC Div. B 9.5.3C.1. in the code viewer
OBC Div. B 9.5.3D.1. Areas of Bedrooms
(1)Except as provided in Articles 9.5.3D.2. and 9.5.3D.3., bedrooms in dwelling units shall have an area not less than 7m² where built-in cabinets are not provided and not less than 6m^2 where built-in cabinets are provided.
Open OBC Div. B 9.5.3D.1. in the code viewer
OBC Div. B 9.5.3D.2. Areas of Master Bedrooms
(1)Except as provided in Article 9.5.3D.3., at least one bedroom in every dwelling unit shall have an area of not less than 9.8 m² where built-in cabinets are not provided and not less than 8.8 m² where built-in cabinets are provided.
Open OBC Div. B 9.5.3D.2. in the code viewer
OBC Div. B 9.5.3E.1. Combined Living, Dining, Bedroom and Kitchen Spaces
(1)Despite Subsections 9.5.3A. to 9.5.3D.., where living, dining, bedroom and kitchen spaces are combined in a dwelling unit that contains sleeping accommodation for not more than two persons, the area of the combined spaces shall be not less than 13.5 m² .
Open OBC Div. B 9.5.3E.1. in the code viewer
OBC Div. B 9.5.3D.4. Areas of Other Sleeping Rooms
(1)Sleeping rooms other than in dwelling units shall have an area not less than 7 m² per person for single occupancy and 4.6 m² per person for multiple occupancy.
Open OBC Div. B 9.5.3D.4. in the code viewer
OBC Div. B Table 9.7.2.3. Glass Areas for Rooms of Residential Occupancy — Forming Part of Sentence 9.7.2.3.(1)
Table 9.7.2.3 — Glass Areas for Rooms of Residential Occupancy — Forming Part of Sentence 9.7.2.3.(1) Location | Minimum Unobstructed Glass Area — With No Electric Lighting | Minimum Unobstructed Glass Area — With Electric Lighting Laundry, basement recreation room, unfinished basement | 4% of area served | Windows not required Water-closet room | 0.37 m² | Windows not required Kitchen space | 10% of area served | Windows not required Kitchen alcove | 10% of area served | Windows not required Living rooms and dining rooms | 10% of area served | 10% of area served Bedrooms and other finished rooms not mentioned above | 5% of area served[1] | 5% of area served[1] Notes to Table 9.7.2.3.: (1) See Subsection 9.9.10.
Open OBC Div. B Table 9.7.2.3. in the code viewer
OBC Div. B 3.7.2.1. Window Areas
(1)Except as provided in Sentences (2) and (3) or otherwise permitted, every room used for sleeping in any building, and every principal room such as living room, dining room or combination of them in dwelling units shall be provided with windows having areas conforming to Part 9, except that Article 9.9.10.1. does not apply. (See Note A-3.7.2.1.(1))
(2)Long-term care homes shall have,
(a)in an activity room, a sitting room or a lounge, one or more windows with a total unobstructed glass area, exclusive of skylights, of not less than 10% of the area of the room, and
(b)in a residents' sleeping room, one or more windows that
(i)have a total unobstructed glass area, exclusive of skylights, of not less than 10% of the area of the room,
(ii)open to the outdoors and have a total unobstructed glass area, exclusive of skylights, of not less than 5% of the area of the room, and
(iii)are installed with the bottom edge of the glass of every window not more than 660 mm above the floor.
(3)Play activity rooms in a child care facility and work areas in live/work units shall have one or more windows that conform to Clause (2)(a).
Open OBC Div. B 3.7.2.1. in the code viewer
OBC Div. B 9.6.1.4. Types of Glass and Protection of Glass
(1)Glass sidelights greater than 500 mm wide that could be mistaken for doors, glass in storm doors and glass in sliding doors within or at every entrance to a dwelling unit and in public areas shall be
(a)safety glazing of the tempered or laminated type conforming to CAN/CGSB-12.1, "Safety Glazing," or
(b)wired glass conforming to CAN/CGSB-12.11-M, "Wired Safety Glass."
(2)Except as provided in Sentence (4), glass in entrance doors to dwelling units and in public areas, other than the entrance doors described in Sentence (1), shall be safety glazing or wired glass of the type described in Sentence (1) where the glass area exceeds 0.5m^2 and extends to less than 900 mm from the bottom of the door.
(3)Except as provided in Sentence (4), transparent panels that could be mistaken as a means of egress shall be protected by barriers or railings.
(4)Sliding glass partitions that separate a public corridor from an adjacent occupancy and that are open during normal working hours need not conform to Sentences (2), (3) and (5), except that such partitions shall be suitably marked to indicate their existence and position.
(5)Except as provided in Sentence (4), every glass or transparent door accessible to the public shall be equipped with hardware, bars or other permanent fixtures designed so that the existence and position of such doors is readily apparent.
(6)Glazing used for a shower or bathtub enclosure shall conform to Class A of CAN/CGSB-12.1, "Safety Glazing."
Open OBC Div. B 9.6.1.4. in the code viewer
OBC Div. B 9.7.5.2. Resistance to Forced Entry for Doors
(1)Except for exterior doors to garages and to other ancillary spaces, this Article applies to
(a)swinging entrance doors to dwelling units,
(b)swinging doors between dwelling units and attached garages or other ancillary spaces, and
(c)swinging doors that provide access directly or indirectly from a storage garage to a dwelling unit. (See Note A-9.7.5.2.(1))
(2)Doors, frames and hardware that conform to a security level of at least Grade 10 as described in the Annex to ASTM F476, "Standard Test Methods for Security of Swinging Door Assemblies," are not required to conform to Sentences (3) to (7). (See Note A-9.7.5.2.(2))
(3)Except as permitted in Sentence (2), wood doors as described in Sentence (1) shall
(a)be solid core or stile-and-rail type,
(b)be not less than 45 mm thick, and
(c)if of the stile-and-rail type, have a panel thickness of not less than 19 mm, with a total panel area not more than half of the door area.
(4)Except as permitted in Sentence (2), doors described in Sentence (1) shall be provided with
(a)a deadbolt lock with a cylinder having no fewer than 5 pins, and
(b)a bolt throw not less than 25 mm long, protected with a solid or hardened free-turning ring or beveled cylinder housing. (See Article 9.9.6.7.)
(5)Except as permitted in Sentence (2), an inactive leaf in double doors used in locations specified in Sentence (1) shall be provided with heavy-duty bolts top and bottom having an engagement of not less than 15 mm.
(6)Except as permitted in Sentence (2), hinges for doors described in Sentence (1) shall be fastened
(a)to wood doors with wood screws not less than 25 mm long and to wood frames with wood screws such that at least 2 screws per hinge penetrate not less than 30 mm into solid wood, or
(b)to metal doors and metal frames with machine screws not smaller than No. 10 and not less than 10 mm long. (See Note A-9.7.5.2.(6))
(7)Strikeplates for deadbolts described in Sentence (4) shall be fastened
(a)to wood frames with wood screws that penetrate not less than 30 mm into solid wood, or
(b)to metal frames with machine screws not smaller than No. 8 and not less than 10 mm long. (See Note A-9.7.5.2.(6))
(8)Except for storm doors or screen doors, doors described in Sentence (1) that swing outward shall be provided with hinges or pins so that the doors cannot be removed when they are in the closed position. (See Note A-9.7.5.2.(8))
(9)Solid blocking shall be provided on both sides at the lock height between the jambs for doors described in Sentence (1) and the structural framing so that the jambs will resist spreading by force.
Open OBC Div. B 9.7.5.2. in the code viewer
OBC Div. B 9.7.5.3. Resistance to Forced Entry for Windows
(1)In dwelling units, windows, any part of which is located within 2 m of adjacent ground level, shall conform to the requirements for resistance to forced entry as described in Clause 5.3.6 of AAMA/WDMA/CSA 101/I.S.2/A440, "North American Fenestration Standard/Specification for windows, doors, and skylights." (See Note A-9.7.5.3.(1))
Open OBC Div. B 9.7.5.3. in the code viewer
OBC Div. B Table 9.8.4.1. Rise for Rectangular Treads, Tapered Treads and Winders and Run for Rectangular Treads — Forming Part of Sentences 9.8.4.1.(1) and 9.8.4.2.(1)
Table 9.8.4.1 — Rise for Rectangular Treads, Tapered Treads and Winders and Run for Rectangular Treads — Forming Part of Sentences 9.8.4.1.(1) and 9.8.4.2.(1) Stair Type | Max. Rise, mm, for All Steps | Min. Rise, mm, for All Steps | Max. Run, mm, for Rectangular Treads | Min. Run, mm, for Rectangular Treads Private stairs[1] | 200 | 125 | 355 | 255 Public stairs[2] | 180 | 125 | no limit | 280 Service stairs[3] | no limit | 125 | 355 | no limit Stairs to unoccupied attic space[4] | no limit | 125 | 355 | no limit Stairs to crawl spaces | no limit | 125 | 355 | no limit Stairs that serve mezzanines not exceeding 20 m² within live/work units | no limit | 125 | 355 | no limit Notes to Table 9.8.4.1.: (1) Private stairs are: (a) interior stairs within a house with a secondary suite or an individual dwelling unit, (b) exterior stairs serving a house with a secondary suite or an individual dwelling unit, and (c) exterior stairs serving a garage that serves a house with a secondary suite or an individual dwelling unit. (2) Public stairs are all stairs not described as service stairs or private stairs. (3) Service stairs are stairs that serve areas used only as service rooms or service spaces. (4) Stairs to unoccupied attic space are stairs that serve attics containing no storage or living space.
Open OBC Div. B Table 9.8.4.1. in the code viewer
OBC Div. B 9.8.3.3. Maximum Height of Stairs
(1)The vertical height of any flight of stairs shall not exceed 3.7 m.
Open OBC Div. B 9.8.3.3. in the code viewer
OBC Div. B 9.8.2.2. Height Over Stairs
(1)The clear height over stairs shall be measured vertically, over the clear width of the stair, from a straight line tangent to the tread and landing nosings to the lowest point above. (See Note A-3.4.3.4.)
(2)Except as provided in Sentences (3) and (4) and Article 9.8.4.7., the clear height over stairs shall not be less than 2,050 mm.
(3)Except as provided in Article 9.8.4.7., the clear height over stairs serving a single dwelling unit or a house with a secondary suite including their common spaces shall not be less than 1,950 mm.
(4)The clear height over stairs that are located under beams and ducting in secondary suites shall not be less than 1,850 mm.
Open OBC Div. B 9.8.2.2. in the code viewer
OBC Div. B 9.8.5.4. Ramp Slope
(1)The slope of ramps shall be not more than
(a)1 in 10 for exterior ramps,
(b)1 in 10 for interior ramps serving residential occupancies,
(c)1 in 6 for industrial occupancies, and
(d)1 in 8 for all other occupancies.
Open OBC Div. B 9.8.5.4. in the code viewer
OBC Div. B 9.8.7.4. Height of Handrails
(1)The height of handrails on stairs and ramps shall be measured vertically from the top of the handrail to
(a)a straight line drawn tangent to the tread nosings of the stair served by the handrail, or
(b)the surface of the ramp, floor or landing served by the handrail.
(2)Except as provided in Sentence (3), Clause 3.8.3.4.(1)(e) and Sentence 9.8.4.7.(1), required handrails shall be 865 mm to 1,070 mm high.
(3)Handrails installed in addition to required handrails need not comply with Sentence (2).
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OBC Div. B 9.8.8.3. Height of Guards
(1)Except as provided in Sentences (2) to (3.1), all guards shall be not less than 1,070 mm high.
(2)All guards within dwelling units or within houses with a secondary suite including their common spaces shall be not less than 900 mm high.
(3)Exterior guards serving not more than one dwelling unit or a house with a secondary suite including their common spaces shall be not less than 900 mm high where the walking surface served by the guard is not more than 1,800 mm above the finished ground level.
(3.1)The height of guards for exterior stairs and landings more than 10 m above adjacent ground level shall be not less than 1,500 mm.
(4)The height of guards for flights of steps shall be measured vertically from the top of the guard to a line drawn through the tread nosing served by the guard.
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OBC Div. B 9.8.8.5. Openings in Guards
(1)Except as permitted in Sentences (3) and (4), openings through guards shall be of a size that prevents the passage of a spherical object having a diameter of 100 mm. (See Note A-9.8.8.5.(1) and (3))
(2)Except for guards that serve industrial occupancies, the triangular openings formed by stair risers, stair treads and the bottom element of a required guard shall be of a size that prevents the passage of a 150 mm diam sphere.
(3)Except where they serve storage garages, guards in industrial occupancies are permitted to consist of
(a)a top railing, and
(b)one or more horizontal intermediate rails spaced such that the size of the openings through the guard prevents the passage of a spherical object having a diameter of 535 mm. (See Note A-9.8.8.5.(1) and (3))
(4)Openings through any guard that is not required by Article 9.8.8.1. and that serves an occupancy other than industrial occupancy, shall be of a size that
(a)prevents the passage of a spherical object having a diameter of 100 mm, or
(b)permits the passage of a spherical object having a diameter of 200 mm. (See Note A-9.8.8.5.(4))
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OBC Div. B 9.8.8.1. Required Guards
(1)Except as provided in Sentence (2) and except at the leading edge at the top of a flight, every surface to which access is provided, including but not limited to flights of steps and ramps, exterior landings, porches, balconies, mezzanines, galleries and raised walkways, shall be protected by a guard on each side that is not protected by a wall for the length where the difference in elevation is more than 600 mm between the walking surface and the adjacent surface within 1.2 m.
(2)Guards are not required
(a)at loading docks,
(b)at floor pits in repair garages, or
(c)where access is provided for maintenance purposes only.
(3)Doors in buildings of residential occupancy, where the finished floor on one side of the door is more than 600 mm above the floor or other constructed surface or ground level on the other side of the door, shall be protected by
(a)a guard, or
(b)a mechanism capable of controlling the free swinging or sliding of the door so as to limit any clear unobstructed opening to not more than 100 mm.
(4)Except as provided in Sentence (5), openable windows in buildings of residential occupancy shall be protected by
(a)a guard, or
(b)a mechanism that can only be released with the use of tools or special knowledge to control the free swinging or sliding operation of the openable part of the window so as to limit any clear unobstructed opening to not more than 100 mm measured either vertically or horizontally. (See Note A-9.8.8.1.(4))
(5)Windows need not be protected in accordance with Sentence (4), where the bottom edge of the openable portion of the window is located
(a)more than 900 mm above the finished floor, or
(b)less than 1,800 mm above the floor or ground on the other side of the window. (See Note A-9.8.8.1.(4))
(6)Except as provided in Sentence (7), glazing installed over stairs, ramps and landings that extends to less than 1,070 mm above the surface of the treads, ramp or landing shall be
(a)protected by guards in accordance with this Subsection, or
(b)non-openable and designed to withstand the specified lateral loads for guards as provided in Article 4.1.5.14.
(7)In dwelling units, glazing installed over stairs, ramps and landings that extends to less than 900 mm above the surface of the treads, ramp or landing shall be
(a)protected by guards in accordance with this Subsection, or
(b)non-openable and designed to withstand the specified lateral loads for guards as provided in Article 4.1.5.14.
(8)Glazing installed in public areas that extends to less than 1 m from the floor and is located above the second storey in buildings of residential occupancy shall be
(a)protected by guards in accordance with this Subsection, or
(b)non-openable and designed to withstand the specified lateral loads for guards as provided in Article 4.1.5.14.
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OBC Div. B 9.8.8.4. Guards for Floors and Ramps in Garages
(1)Except for floors of garages referred to in Section 9.35., where garage floors or ramps are 600 mm or more above the adjacent ground or floor level, every opening through a garage floor and the perimeter of floors and ramps that have no exterior walls shall be provided with
(a)a continuous curb not less than 140 mm in height, and
(b)a guard not less than 1,070 mm above the floor level.
(2)Vehicle guardrails shall be designed and constructed to withstand the loading values stipulated in Sentence 4.1.5.15.(1). (See Note A-4.1.5.14. and 4.1.5.15.(1))
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OBC Div. B 9.8.9.6. Finish for Treads, Landings and Ramps
(0.1)Except as required by Sentence (2), the finish for treads, landings and ramps shall be
(a)wear-resistant,
(b)slip-resistant, and
(c)smooth, even and free from open defects.
(1)The finish for treads and landings of interior stairs in dwelling units, other than stairs to unfinished basements, shall consist of hardwood, vertical grain softwood, resilient flooring or other material providing equivalent performance.
(2)Treads and landings of interior and exterior stairs and ramps, other than those within dwelling units or within houses with a secondary suite including their common spaces, shall have a slip-resistant finish or be provided with slip-resistant strips that extend not more than 1 mm above the surface.
(3)Stairs and ramps, except those serving a house with a secondary suite, an individual dwelling unit, service rooms or service spaces, shall have a colour contrast or a distinctive visual pattern to demarcate
(a)the leading edge of the treads,
(b)the leading edge of the landing, and
(c)the beginning and end of a ramp.
(4)Except for stairs serving a house with a secondary suite, an individual dwelling unit, service rooms or service spaces, a tactile attention indicator conforming to Article 3.8.3.18. shall be installed
(a)at the top of the stairs, starting one tread depth back from the edge of the top stair, and
(b)at the leading edge of landings where a doorway opens onto stairs, starting one tread depth back from the edge of the landing.
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OBC Div. B 9.8.9.1. Loads on Stairs and Ramps
(1)Except as specified in Articles 9.8.9.4. and 9.8.9.5., stairs and ramps shall be designed for strength and rigidity under uniform loading criteria to support specified loads of
(a)1.9 kPa for stairs and ramps serving not more than one dwelling unit or a house with a secondary suite including their common spaces, and
(b)4.8 kPa for other stairs and ramps.
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OBC Div. B 9.27.8.2. Thickness
(1)Plywood cladding shall be not less than 6 mm thick when applied directly to sheathing.
(2)When applied directly to framing or over furring strips, plywood cladding thickness shall conform to Table 9.27.8.2.
(3)The thickness of grooved or textured plywood cladding shall be measured at the point of least thickness.
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OBC Div. B 9.27.6.2. Thickness and Width
(1)Drop, rustic, novelty, lapped board and vertical wood siding shall be not less than 14.3 mm thick and not more than 286 mm wide.
(2)Bevel siding shall be
(a)not less than 5 mm thick at the top, and
(b)not less than
(i)12 mm thick at the butt for siding 184 mm or less in width, and
(ii)14.3 mm thick at the butt for siding wider than 184 mm.
(3)Bevel siding shall be not more than 286 mm wide.
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OBC Div. B 9.27.12.1. Material Standards
(1)Vinyl siding shall conform to ASTM D3679, "Standard Specification for Rigid Poly (Vinyl Chloride) (PVC) Siding."
(2)Insulated vinyl siding shall conform to ASTM D7793, "Standard Specification for Insulated Vinyl Siding."
(3)Rigid vinyl soffits shall conform to ASTM D4477, "Standard Specification for Rigid (Unplasticized) Poly(Vinyl Chloride) (PVC) Soffit."
(4)Where vinyl siding, insulated vinyl siding or rigid vinyl soffits are required to have a flame-spread rating, the rating shall be determined in accordance with CAN/ULC-S102.2, "Standard Method of Test for Surface Burning Characteristics of Flooring, Floor Coverings, and Miscellaneous Materials and Assemblies."
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OBC Div. B Table 9.29.5.3. Spacing of Supports for Gypsum Board Conforming to Sentence 9.29.5.2.(1) (Except Sections 9 and 12 of ASTM C1396 / C1396M)
Table 9.29.5.3. — Spacing of Supports for Gypsum Board Conforming to Sentence 9.29.5.2.(1) (Except Sections 9 and 12 of ASTM C1396 / C1396M) Forming Part of Sentence 9.29.5.3.(1) Thickness, mm | Orientation of Board to Framing | Maximum Spacing of Supports, mm o.c. (Walls) | Maximum Spacing of Supports, mm o.c. (Ceilings – Painted Finish) | Maximum Spacing of Supports, mm o.c. (Ceilings – Water-Based Texture Finish) 9.5 | parallel | N/A | N/A | N/A 9.5 | perpendicular | 400 | 400 | N/A 12.7 | parallel | 600 | 400 | N/A 12.7 | perpendicular | 600 | 600 | 400 15.9 | parallel | 600 | 400 | N/A 15.9 | perpendicular | 600 | 600 | 600 Table 9.29.5.3. (continued) — Spacing of Supports for Gypsum Board Conforming to Clause 9.29.5.2.(1)(b) (Only Section 12 of ASTM C1396 / C1396M) Thickness, mm | Orientation of Board to Framing | Maximum Spacing of Supports, mm o.c. (Walls) | Maximum Spacing of Supports, mm o.c. (Ceilings – Painted Finish) | Maximum Spacing of Supports, mm o.c. (Ceilings – Water-Based Texture Finish) 12.7 | parallel | 600 | 400 | N/A 12.7 | perpendicular | 600 | 600 | 600
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OBC Div. B Table 9.29.5.5. Minimum Penetration, mm - Forming Part of Sentence 9.29.5.5.(1)
Table 9.29.5.5. — Minimum Penetration, mm - Forming Part of Sentence 9.29.5.5.(1) Forming Part of Sentence 9.29.5.5.(1) Required Fire-Resistance Rating of Assembly | Walls (Nails) | Walls (Screws) | Ceilings (Nails) | Ceilings (Screws) Not required | 20 | 15 | 20 | 15 45 min | 20 | 20 | 30 | 30 1 h | 20 | 20 | 45 | 45 1.5 h | 20 | 20 | 60 | 60
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OBC Div. B 9.29.5.9. Spacing of Screws
(1)For single-layer application on a ceiling, screws shall be spaced not more than 300 mm o.c. on ceiling supports.
(2)Where the ceiling sheets are supported by the wall sheets around the perimeter of the ceiling, this support may be considered as equivalent to screwing at this location.
(3)Except as required by Sentence (4), for single-layer application on walls, screws shall be spaced
(a)not more than 300 mm o.c. on vertical wall supports where the supports are more than 400 mm o.c., or
(b)not more than 400 mm o.c. on vertical wall supports where the supports are not more than 400 mm o.c.
(4)Except as provided in Sentence (5), for single-layer application on walls, where gypsum board provides required bracing in braced wall panels, lateral support for studs, or fire protection, screws shall be spaced not more than 300 mm o.c. on
(a)vertical wall supports, and
(b)top and bottom plates. (See Article 9.23.10.2. and Section 9.10.)
(5)Where a fire-resistance rating is determined based on Table 1 of MMAH Supplementary Standard SB-3, "Fire and Sound Resistance Tables," Sentence (4) need not apply for the purpose of fire protection.
(6)Screws shall be located not less than 10 mm from the edge of the board.
(7)Screws shall be driven so that the heads do not puncture the paper.
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OBC Div. B 9.29.5.4. Support of Insulation
(1)Gypsum board supporting insulation shall be not less than 12.7 mm thick.
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OBC Div. B 9.33.6.2. Materials in Air Duct Systems
(1)Except as provided in Sentences (2) to (6.2) and in Article 3.6.4.3., all ducts, duct connectors, associated fittings and plenums used in air duct systems shall be constructed of steel, aluminum alloy, copper, clay or similar noncombustible material.
(2)Ducts, associated fittings and plenums are permitted to contain combustible material provided they
(a)conform to the appropriate requirements for Class 1 duct materials in CAN/ULC-S110, "Standard Methods of Test for Air Ducts,"
(b)conform to Article 3.1.5.18. and Subsection 3.1.9.,
(c)are not used in vertical runs serving more than 2 storeys, and
(d)are not used in air duct systems in which the air temperature may exceed 120°C.
(3)Duct sealants shall have a flame-spread rating of not more than 25 and a smoke developed classification of not more than 50.
(4)Duct connectors that contain combustible materials and that are used between ducts and air outlet units shall
(a)conform to the appropriate requirements for Class 1 air duct materials in CAN/ULC-S110, "Standard Methods of Test for Air Ducts,"
(b)be limited to 4 m in length,
(c)be used only in horizontal runs, and
(d)not penetrate required fire separations.
(5)Combustibleducts that are part of a duct system carrying only ventilation air and that are contained entirely within a dwelling unit need not comply with the requirements of Sentences (1) to (4).
(6)Except as provided in Sentences 9.33.6.13.(2) and (3), ducts that are part of a return-air duct system and that are contained entirely within a dwelling unit need not comply with the requirements of Sentences (1) to (4).
(6.1)All ductwork and fittings shall be constructed and installed in conformance with SMACNA Manuals and ASHRAE Handbooks.
(6.2)All duct materials and fittings shall be
(a)suitable for exposure to the temperature and humidity of the air being conveyed, and
(b)resistant to corrosion due to contaminants in the air being conveyed in the duct.
(7)Materials referred to in Sentences (1) to (6.2), when used in a location where they may be subjected to excessive moisture, shall
(a)have no appreciable loss of strength when wet, and
(b)be corrosion-resistant.
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OBC Div. B 9.33.6.4. Coverings, Linings and Insulation
(1)Reserved.
(2)Reserved.
(3)Reserved.
(4)Reserved.
(5)Except as permitted in Sentences (6) and (7), foamed plastic insulation shall not be used as part of an air duct or for insulating an air duct.
(6)Foamed plastic insulation conforming to Article 9.25.2.2. is permitted to be used to insulate a galvanized steel, stainless steel or aluminum air duct, provided
(a)the foamed plastic insulation applied to supply ductwork is not less than 3 m from the furnace bonnet,
(b)the temperature within the ductwork where the insulation is installed is not greater than 50°C,
(c)duct joints are taped with a product conforming to Sentence 9.33.6.3.(1),
(d)return air plenums are separated from the foamed plastic insulation, and
(e)the foamed plastic insulation is protected in accordance with Article 9.10.17.10.
(7)Foamed plastic insulation is permitted to be used in a ceiling space that acts as a return air plenum provided the foamed plastic insulation is protected from exposure to the plenum in accordance with Sentence 3.1.5.14.(4).
(8)Reserved.
(9)Linings of ducts shall be installed so that they will not interfere with the operation of volume or balancing dampers or of fire dampers, fire stop flaps and other closures.
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OBC Div. B 9.33.7.2. Surface Temperature
(1)The exposed surface temperature of a steam or hot water radiator shall not exceed 70°C unless precautions are taken to prevent human contact.
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OBC Div. B 9.32.3.9. Application of Carbon Monoxide Alarms
(1)Article 9.32.3.9A. applies to every building that
(a)contains a supply duct, and contains a fuel-burning appliance or a storage garage, or
(b)contains a residential occupancy and is served by a forced-air fuel-burning appliance not contained within the building.
(2)Articles 9.32.3.9B. and 9.32.3.9C. apply to every building.
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OBC Div. B 9.32.3.9C. Installation and Conformance to Standards
(1)The carbon monoxide alarms required by Articles 9.32.3.9A. and 9.32.3.9B. shall
(a)except as permitted in Sentence (2), be permanently connected to an electrical circuit and shall have no disconnect switch between the overcurrent device and the carbon monoxide alarm,
(b)in case the regular power supply to the carbon monoxide alarm is interrupted, be provided with a battery as an alternative power source that can continue to provide power to the carbon monoxide alarm for a period of not less than 8 h in the standby condition, followed by the operation of the carbon monoxide alarm for an alarm signal for at least 12 h,
(c)be wired so that
(i)activation of one carbon monoxide alarm within a suite of residential occupancy will activate all carbon monoxide alarms within the suite,
(ii)activation of one carbon monoxide alarm within a house with a secondary suite will activate all carbon monoxide alarms within the house with a secondary suite including their common spaces, and
(iii)activation of one carbon monoxide alarm located in a public corridor serving suites of residential occupancy will activate all carbon monoxide alarms within the corridor.
(d)be audible within sleeping rooms when the intervening doors are closed, where located adjacent to a sleeping room in a suite of residential occupancy, and
(e)conform to
(i)CAN/CSA-6.19, "Residential Carbon Monoxide Alarming Devices," or
(ii)UL 2034, "Single and Multiple Station Carbon Monoxide Alarms."
(2)Where the building is not supplied with electrical power, carbon monoxide alarms are
(a)are permitted to be battery operated, and
(b)need not have a visual signaling component.
(3)Except as permitted in Sentence (2), the carbon monoxide alarms required by Articles 9.32.3.9A. and 9.32.3.9B. shall have a visual signalling component conforming to the requirements in 18.5.3. (Light, Color and Pulse Characteristics) of NFPA 72, "National Fire Alarm and Signaling Code".
(4)The luminous intensity for visual signaling components required by Sentence (3) that are installed in sleeping rooms or combined living and sleeping areas shall be a minimum of 175 cd.
(5)The visual signaling component required by Sentence (3) need not
(a)be integrated with the carbon monoxide alarm provided it is interconnected to it,
(b)be on battery backup, or
(c)have synchronized flash rates, when installed in a dwelling unit.
(6)The carbon monoxide alarms required by Articles 9.32.3.9A. and 9.32.3.9B. shall be installed
(a)at the manufacturer's recommended height, or
(b)in the absence of specific instructions, on or near the ceiling.
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OBC Div. B 9.34.2.1. Lighting of Entrances
(1)An exterior lighting outlet with fixture controlled by a wall switch located within the building shall be provided at every entrance to buildings of residential occupancy.
(2)The exterior lighting outlet with fixture required by Sentence (1) may be controlled by a wall switch or panel accessible to authorized personnel only, where it serves,
(a)a building entrance serving multiple suites of residential occupancy,
(b)multiple dwelling unit entrances,
(c)hotels, or
(d)motels.
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OBC Div. B 9.34.2.7. Public and Service Areas
(1)Every public or service area in buildings, including a recreational camp and a camp for housing of workers, shall have lighting outlets with fixtures controlled by a wall switch or panel to illuminate such areas.
(2)When provided by incandescent lighting, illumination required in Sentence (1) shall conform to Table 9.34.2.7. (See Article 9.9.12.2. for lighting in means of egress.)
(3)When other types of lighting are used, illumination equivalent to that shown in Table 9.34.2.7. shall be provided.
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OBC Div. B Table 9.34.2.7. Lighting for Public Areas - Forming Part of Sentences 9.34.2.7.(2) and (3)
Table 9.34.2.7. Lighting for Public Areas - Forming Part of Sentences 9.34.2.7.(2) and (3) Forming Part of Sentences 9.34.2.7.(2) and (3) Room or Space | Minimum Illumination, lx | Minimum Lighting Power Density, W/m² of floor area Storage rooms | 50 | 5 Service rooms and laundry areas | 200 | 20 Garages | 50 | 5 Public water closet rooms | 100 | 10 Service hallways and stairways | 50 | 5 Recreation rooms | 100 | 10 Hallways, corridors, stairways and sleeping areas in recreational camps and camps for housing of workers | 100 | 10 Kitchen in recreational camps and camps for housing of workers | 500 | 50 All other rooms in recreational camps and camps for housing of workers | 250 | 25
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