H-6

Question 1

What are the functions of a ceiling joist?

Answer 1

-tie the bottoms of rafters together
-tie the supporting walls together
-support the interior ceiling finish

Question 2

Which type of roof creates the most tension in ceiling joists: low-slope roofs or high-slope roofs?

Answer 2

low-slope

Question 3

What is the difference between “overhang” and “projection”

Answer 3

-overhand is measured along the length of the rafter;
-projection is measured horizontally.

Question 4

What is a “fly rafter”?

Answer 4

rafter outside the gable end of the roof (also known as barge rafter)

Question 5

What is the unit of run when using the imperial system?

Answer 5

12”

Question 6

What is the unit of run when using the Frederickson square?

Answer 6

250mm

Question 7

What is a “working point”?

Answer 7

Working points are the marks on the rafters where measurements are made and cuts are laid out.

Question 8

What is the difference between the “line length” and the “run” of a rafter?

Answer 8

Line length is measured along the rafters length. The run is the rafter’s horizontal span.

Question 9

What is the difference between a “ridge board” and a “ridge beam”?

Answer 9

A ridge board is used to align the tops of the common rafters. A ridge beam is used to support roof joists at the ridge.