Floor, Wall & Roof Framing Flashcards

What does 'dead load' mean in the context of structural framing?

Answer: The permanent static weight of the building structure and fixed components

Dead load is the permanent, static weight of all building materials — framing, sheathing, insulation, roofing, drywall, flooring, and fixed mechanical equipment. It does not change once construction is complete and must be supported continuously.

According to NBC Part 9, what is the minimum R-value of attic insulation required for most of Canada (Zone 6 and above)?

Answer: R-40 (RSI 7.0)

NBC 2020 Part 9 requires minimum RSI 7.0 (approximately R-40) for attic/ceiling insulation in Climate Zone 6, which covers most of Canada's populated regions. Higher zones require more. This is part of the enhanced energy efficiency requirements.

What is a cantilevered floor joist and what special consideration is required?

Answer: A joist that extends beyond its support — the backspan must be at least twice the cantilever length

A cantilever extends a floor beyond the supporting wall or beam. The backspan (the portion inside) must be at least twice the cantilever length to prevent rotation and uplift at the interior support. Engineering review is needed for longer cantilevers.

When framing around a stairwell opening in a floor system, what is the name of the doubled joist that runs parallel to the opening to carry the header?

Answer: Trimmer joist (also called a trimmer or stringer joist)

Trimmer joists (or stringers) run parallel to the main joists and frame the sides of the stairwell opening. They are doubled to carry the load from the doubled header (which spans the short direction of the opening) plus the tail joists.

What is the purpose of a temporary wall built parallel to and below a load-bearing wall during a floor system repair or renovation?

Answer: To transfer structural loads from the floor system to an alternate path while the bearing wall or joists are modified

A temporary shoring wall carries the loads normally carried by the structure being modified. It must be designed to carry dead and live loads, be supported on adequate bearing, and remain in place until the permanent structure is restored and approved.

What is the minimum slope required for a roof to be considered a sloped (non-flat) roof and use standard shingles per the NBC?

Answer: 1:6 (approximately 100 mm rise per 600 mm run)

The NBC requires a minimum slope of 1:6 (approximately 1 in 6, or about a 2:12 pitch) for asphalt shingle application. Below this slope, special low-slope roofing systems (modified bitumen, EPDM, etc.) with underlayment must be used.