403A Stair Construction 2

Question 1

What characterizes a 'housed stringer' (closed stringer) in stair construction?

Accepted Answer

Treads and risers fit into routed grooves on the inside face of the stringer

Answer

Notches are cut along the top edge to receive treads and risers

Answer

The stringer is concealed entirely within a finished wall

Answer

The stringer is fabricated from engineered lumber

Question 2

What is the maximum allowable variation in riser height within a single flight of stairs according to the NBC?

Accepted Answer

5mm

Answer

3mm

Answer

8mm

Answer

10mm

Question 3

What is the maximum permitted opening between balusters on a stair guard?

Accepted Answer

100mm

Answer

75mm

Answer

125mm

Answer

150mm

Question 4

Under the NBC, a guard must be provided when the stair or surface is adjacent to a drop of more than:

Accepted Answer

600mm

Answer

450mm

Answer

750mm

Answer

900mm

Question 5

What is the minimum clear width required for a residential staircase under the NBC?

Accepted Answer

860mm

Answer

760mm

Answer

900mm

Answer

1000mm

Question 6

A 'winder' tread is used in stair construction primarily to:

Accepted Answer

Allow the staircase to change direction without a full landing

Answer

Provide additional structural support to the stringer

Answer

Increase headroom at the bottom of the staircase

Answer

Reduce the total number of risers required

Question 7

What is the primary purpose of an intermediate landing in a long staircase?

Accepted Answer

To provide a level rest platform and satisfy code limits on continuous flight length

Answer

To increase the total rise of the staircase

Answer

To reduce the number of stringers required

Answer

To meet minimum headroom clearance requirements