403A Roofing Systems

Question 1

What is the minimum roof slope generally recommended for asphalt shingle installation in Canada?

Accepted Answer

4:12

Answer

1:12

Answer

2:12

Answer

6:12

Question 2

What is ice and water shield membrane and where is it required in Canadian roofing?

Accepted Answer

A self-adhering waterproof membrane applied at vulnerable areas like eaves and valleys

Answer

A type of flashing for chimneys only

Answer

An insulation product installed over roof sheathing

Answer

A vapour barrier placed under the roof deck

Question 3

What is the standard exposure (amount of shingle visible) for a typical three-tab asphalt shingle?

Accepted Answer

127 mm (5 in.)

Answer

100 mm (4 in.)

Answer

152 mm (6 in.)

Answer

178 mm (7 in.)

Question 4

What is the purpose of a ridge vent on a sloped roof?

Accepted Answer

To allow warm, moist air to exhaust from the attic at the highest point

Answer

To prevent wind uplift on the ridge cap

Answer

To strengthen the ridge beam

Answer

To direct rainwater away from the ridge

Question 5

What is a roof truss and how does it differ from conventional rafter framing?

Accepted Answer

A truss is a prefabricated triangulated framework that spans the full building width without interior bearing walls

Answer

A truss is a curved structural member used in arched roofs

Answer

A truss is a type of heavy timber beam used in post-and-beam construction

Answer

A truss is a metal connector used to join rafters at the ridge

Question 6

According to the NBC, what is the minimum attic ventilation ratio for a residential roof in Canada?

Accepted Answer

1:300 of the insulated ceiling area

Answer

1:150 of the insulated ceiling area

Answer

1:500 of the insulated ceiling area

Answer

1:1000 of the insulated ceiling area