Ontario Building Code Exam: Small Buildings

Under OBC 9.15.3.4., what is the minimum width of concrete footings supporting a 3-storey wood-frame exterior wall with no masonry veneer?

• A300 mm
• B350 mm
• C450 mm
• D600 mm

According to OBC 9.12.2.2., what is the minimum depth of foundation below finished grade for a heated building on fine sand or silt to prevent frost damage?

• A1.2 m
• B1.0 m
• C1.4 m
• D1.6 m

Under OBC 9.23.4.1. / 9.4.1.2., what is the maximum allowable elastic deflection for a floor joist supporting a finished gypsum board ceiling?

• AL/180
• BL/240
• CL/360
• DL/480

For structural design under OBC 9.4.2.2., the specified snow load on a roof is calculated using which formula?

• AS = C_b * S_s * S_r
• BS = C_b * S_s + S_r
• CS = S_s + S_r
• DS = S_s / C_b + S_r

Under OBC 9.23.6.1., what is the maximum spacing of anchor bolts used to secure a wood sill plate to a foundation wall?

• A1.2 m
• B1.5 m
• C2.4 m
• D3.0 m

Under OBC Table 9.15.4.2.A., what is the minimum thickness of a concrete foundation wall supporting wood-frame construction where the height of finished backfill exceeds 1.2 m but is not more than 2.1 m, and the wall is laterally supported at the top?

• A150 mm
• B200 mm
• C250 mm
• D300 mm

Under OBC Table 9.23.14.3., what is the minimum thickness of plywood subflooring for floor joists spaced at 400 mm (16 inches) on centre?

• A12.5 mm
• B15.5 mm
• C18.5 mm
• D22.0 mm

According to OBC 9.23.4.2., notches made in the top or bottom of wood floor joists must not exceed what proportion of the joist depth?

• A1/4 of the depth
• B1/3 of the depth
• C1/6 of the depth
• D1/2 of the depth

According to OBC 9.15.3.6., concrete footings must have a thickness that is at least equal to:

• AThe footing projection from the foundation wall
• BDouble the footing projection from the foundation wall
• C100 mm
• D150 mm in all cases

Under OBC 9.23.10.2., wood-frame walls must be braced to resist lateral wind and seismic loads. Which of the following satisfies the prescriptive requirements for bracing exterior walls?

• AOnly interior walls require bracing
• BSheathing conforming to Part 9 or diagonal wood strapping
• CGypsum board applied to one side of the studs only
• DA minimum of 50% wall glazing

In the absence of design values or site-specific testing, what is the default presumptive design bearing pressure for coarse sand under OBC Table 9.4.4.1.?

• A50 kPa
• B75 kPa
• C100 kPa
• D150 kPa

According to OBC 9.14.2.1., foundation drainage tile or pipe must be installed around the perimeter of all foundations enclosing a basement unless:

• AThe foundation is concrete slab-on-grade
• BThe soil is well-drained sand or gravel
• CThe building is located in an urban area with storm sewers
• DThe foundation wall is waterproofed

Under OBC 9.23.9.4., intermediate strapping or bridging is required for wood floor joists when their span exceeds:

• A2.4 m
• B3.6 m
• C4.3 m
• D5.0 m

Under OBC 9.23.9.6., where a non-loadbearing partition parallel to the floor joists is supported by the floor, and the joists are not doubled, what structural action is required?

• AThe joist spacing must be reduced to 300 mm
• BSolid blocking must be installed between the joists at not more than 1.2 m spacing
• CNo action is required as long as the joist span is under 3 m
• DHangers must be used at the ends of the partition joists

According to OBC 9.23.13.8., what is the primary structural purpose of collar ties installed in a wood-frame roof system?

• ATo prevent the ceiling from sagging
• BTo resist wind uplift and prevent the rafters from spreading
• CTo provide a nailing surface for drywall
• DTo brace the ridge board against horizontal movement

Under OBC Table 9.3.1.6.2., what is the minimum compressive strength of concrete required for a residential garage slab-on-grade that is exposed to freeze-thaw cycles?

• A15 MPa
• B20 MPa
• C32 MPa
• D40 MPa

OBC 9.23.12.1. requires lintels to be supported by at least how many jack studs (cripple studs) at each end for a span of 2.5 m?

• A1 jack stud at each end
• B2 jack studs at each end
• C3 jack studs at each end
• DNo jack studs are required if hangers are used

Under OBC 9.23.13.7., when rafters are supported by intermediate purlins to reduce their span, where must these purlins be supported?

• ADirectly on the ceiling joists at any point
• BOn loadbearing walls or strutted to loadbearing partitions
• CDirectly on the subflooring
• DSuspended from the ridge board

According to OBC 9.18.4.1., what is the minimum dimension for an access hatch to a crawl space?

• A500 mm by 700 mm
• B600 mm by 900 mm
• C500 mm by 500 mm
• D450 mm by 600 mm

Under OBC 9.3.2.1., lumber used for structural members (like joists, rafters, and studs) must be:

• ARough-sawn green lumber from any mill
• BGraded and stamped at an authorized lumber grading agency
• CImported hardwood in all cases
• DPressure-treated even for dry interior use

Under OBC 9.10.9.14., what is the minimum fire-resistance rating required for a fire separation between two residential suites in a non-sprinklered building?

• A45 minutes
• B1 hour
• C1.5 hours
• D2 hours

According to OBC 9.10.19.3., smoke alarms in a dwelling unit must be installed on each storey and must meet which of the following power supply and interconnection requirements?

• AThey can be battery-operated only with no connection to each other
• BThey must be hardwired to an electrical circuit with battery backup and interconnected so…
• CThey must be wireless standalone battery units only
• DThey must be connected to the main security panel but do not need battery backup

Under OBC 9.10.18.2., in which of the following locations is a carbon monoxide (CO) alarm mandatory in a residential building?

• AOnly in the mechanical room next to the furnace
• BInside or within 5 metres of the bedroom door of every bedroom, if the building has a fue…
• COnly in the kitchen above the stove
• DOn the exterior wall near the garage entrance only

According to OBC 9.10.17.2., the interior finish of walls and ceilings in a required exit must have a flame-spread rating of not more than:

• A25
• B75
• C150
• D200

Under OBC 9.9.10.1., an egress window in a bedroom must provide an unobstructed opening of not less than 0.35 m² in area, with no dimension less than:

• A300 mm
• B380 mm
• C450 mm
• D500 mm

Under OBC Table 9.8.4.1., what is the maximum rise permitted for a step in a private stair inside a house?

• A180 mm
• B200 mm
• C210 mm
• D225 mm

According to OBC 9.8.8.3., what is the minimum guard height required for an outdoor deck that is situated 2.0 m above the finished ground level?

• A900 mm
• B1070 mm
• C1100 mm
• D1200 mm

Under OBC 9.8.7.3., handrails for stairs must be installed at a height of:

• ANot less than 800 mm and not more than 900 mm
• BNot less than 865 mm and not more than 1070 mm
• CNot less than 900 mm and not more than 1100 mm
• DExactly 1000 mm in all cases

What is the minimum width of an exit stair serving a single dwelling unit according to OBC 9.8.4.8.?

• A800 mm
• B860 mm
• C900 mm
• D1000 mm

Under OBC 9.10.11.1., a firewall that separates two buildings of wood-frame construction must have a fire-resistance rating of not less than:

• A1 hour
• B2 hours
• C3 hours
• D4 hours

According to OBC 9.10.16.1., fire stopping (fireblocking) must be provided in all concealed spaces of wood-frame construction to:

• AProvide additional structural bracing for walls
• BBlock the passage of insects and rodents
• CRestrict the passage of smoke and fire through concealed cavities
• DHold insulation batts in place

Under OBC 9.10.13.13., where a heating or air-conditioning duct passes through a required fire separation, what device must be installed to maintain the integrity of the separation?

• AA backdraft damper
• BA fire damper
• CA vibration isolator
• DA smoke detector

Under OBC 9.10.14.3., spatial separation requirements are based on the 'limiting distance'. How is limiting distance defined?

• AThe distance from a building to the opposite side of a street or lane
• BThe distance from an exposing building face to a property line, the centreline of a stree…
• CThe distance between the front and back entrance doors of a building
• DThe height of the building divided by two

Under OBC 9.9.6.1. and 9.9.6.4., in what direction must an exit door swing if it serves a occupancy capacity of more than 60 persons?

• AInwards (towards the room)
• BOutwards (in the direction of exit travel)
• CIt must slide sideways
• DIt can swing in either direction

According to OBC 9.10.15.5., the maximum percentage of glazed openings (windows) allowed in an exposing building face decreases as:

• AThe building height increases
• BThe limiting distance decreases
• CThe floor area of the building increases
• DThe fire resistance rating of the interior walls increases

According to OBC 9.8.8.5., openings in guards for decks, balconies, and stairs must be sized so that a sphere of what diameter cannot pass through?

• A80 mm
• B100 mm
• C120 mm
• D150 mm

Under OBC 9.10.9.16., what type of door assembly is required in a fire separation separating a public corridor from a residential suite?

• AA standard hollow-core wood door
• BA fire protection rated door (typically 20 minutes) equipped with a self-closing device
• CA sliding glass pocket door
• DA solid metal door with a keyless entry pad but no closer

According to OBC 9.9.9.1., the travel distance from a suite door to an exit in a public corridor must not exceed what distance in a non-sprinklered building?

• A15 m
• B30 m
• C40 m
• D45 m

OBC 9.10.16.2. requires fire stopping to be installed in wood-frame walls at what maximum vertical intervals?

• A1.5 m
• B3.0 m
• C4.5 m
• D6.0 m

Under OBC 9.9.11.1., when is exit signage mandatory in a Part 9 building?

• AIn all single-family homes
• BIn buildings more than 2 storeys in height, or containing an exit corridor serving more t…
• CIn all commercial buildings, and residential buildings containing a shared exit system se…
• DOnly in buildings with a floor area greater than 1000 m²

According to OBC 9.19.1.2., the minimum total vent area for an attic space with a roof slope of 1:6 or greater must be what proportion of the insulated ceiling area?

• A1/100
• B1/150
• C1/300
• D1/500

Under OBC 9.19.1.3., what is the minimum clearance that must be maintained between the top of roof insulation and the underside of the roof sheathing to allow attic ventilation?

• A25 mm
• B50 mm
• C75 mm
• D100 mm

Under OBC 9.13.2.1. and 9.13.3.1., what determines whether a foundation wall requires waterproofing rather than dampproofing?

• AThe height of the foundation wall
• BThe presence of hydrostatic pressure (high water table)
• CThe type of concrete used for the wall
• DWhether the basement is finished or unfinished

According to OBC 9.25.4.1., where must a vapour barrier be installed in relation to the thermal insulation in a wall assembly?

• AOn the exterior (cold) side of the insulation
• BOn the interior (warm) side of the insulation, or sufficiently close to it, to prevent co…
• CDirectly in the middle of the insulation layer
• DVapour barriers are not permitted if air barriers are present

According to OBC 9.25.4.2., a material used as a vapour barrier in a building envelope must have a vapour permeance not greater than:

• A15 ng/(Pa·s·m²)
• B45 ng/(Pa·s·m²)
• C60 ng/(Pa·s·m²)
• D100 ng/(Pa·s·m²)

Under OBC 9.27.3.8., exterior wood siding or other organic cladding must terminate at least how far above the finished ground level (soil)?

• A50 mm
• B100 mm
• C150 mm
• D200 mm

OBCSB-12 (Supplementary Standard SB-12) establishes energy efficiency requirements for Ontario. What is the primary purpose of this standard?

• ATo regulate structural concrete strength in winter
• BTo provide prescriptive and performance compliance paths for building envelope thermal in…
• CTo set fire separation ratings for commercial office towers
• DTo govern electrical wiring safety in small residential buildings