H6 - Roof Framing

Question 1

Which member identified in Figure 1 is a jack rafter?

Answer 1

6

Question 2

Which rafter is #5 in Figure 1?

Answer 2

hip rafter

Question 3

What are cheek cuts?

Answer 3

compound mitre cuts

Question 4

What is a working point?

Answer 4

a theoretical point used to calculate and layout rafters

Question 5

At what working height are you required to have a written fall protection procedure

Answer 5

25’

Question 6

Which construction drawings are most likely to show the roof slope?

Answer 6

Elevation view

Question 7

What are the angles used when drawing rafters for an equal slope, intersecting roof in plan view?

Answer 7

90° and 45°

Question 8

When referring to the BCBC, what information is required to determine rafter sizes?

Answer 8

Species, grade and spacing of rafters, snow loads and run of the common rafter

Question 9

What is the purpose of installing ceiling joists?

Answer 9

To tie rafters together, resisting tension forces and help support ceiling finishes

Question 10

What rafter acts as a sway brace in a hip roof?

Answer 10

End common rafter

Question 11

When calculating theory lengths, in what way will hip rafters and common rafters be equal?

Answer 11

number of units of run

Question 12

What is the length of a unit of run for a common rafter?

Question 13

To mark a plumb line on a hip rafter for a 5:12 roof, the framing square should be set to 5 and what other number?

Answer 13

17

Question 14

What is the shortening for the upper end of a hip rafter?

Answer 14

½ the diagonal thickness of the common

Question 15

How is wood above plate determined for the bird’s mouth on a hip rafter?

Answer 15

Measure the wood above the plate of the common rafter

Question 16

What are the adjustments to determine the actual length of the ridge on a hip roof?

Answer 16

add half the thickness of the common at each end

Question 17

How do you measure the line length for any framing member of a roof?

Answer 17

From working point to working point

Question 18

What is the adjustment at the top end of the end common?

Answer 18

half the thickness of the common

Question 19

What is the shortening at the top end of a jack rafter?

Answer 19

half the diagonal thickness of the hip

Question 20

The layout for the bird’s mouth, overhang and tail cut of the jack rafter, is the same as which of the following?

Answer 20

the common rafters

Question 21

What will be the shortening adjustment for a hip jack that frames into a 4”x12” PSL hip rafter?

Answer 21

2 13/16”

Question 22

The layout along the plate for the location of the first common rafter is measured from the corner of the building to the centre of the rafter. What will this distance be?

Answer 22

the total run of the common

Question 23

When should the ridge board for a roof with an unsupported ridge be installed?

Answer 23

after the first two sets of common rafters, by slipping it up between them

Question 24

What is required for the lower edge of the first row of plywood roof sheathing?

Answer 24

It should be supported

Question 25

What is the spacing for nails along the perimeter of plywood roof sheathing?

Answer 25

6 inches

Question 26

How must the face grain of plywood roof sheathing be installed?

Answer 26

perpendicular to the rafters

Question 27

What is the measurement from the cut side end to the short point to layout the correct angle on a 4’x8’ sheet of plywood roof sheathing for a 6:12 hip roof?

Answer 27

42 15/16” (Run/Hyp x 48")

Question 28

What is the name of the rafter labelled ‘n’?

Answer 28

Valley Rafter

Question 29

What is the name of the rafter labelled ‘p’?

Answer 29

Valley Jack

Question 30

What is the name of the rafter labelled ‘e’?

Answer 30

Hip Valley Cripple Jack

Question 31

Which of the following statements is correct?

Answer 31

The major roof has the widest span

Question 32

Which of the following statements is correct for typical supported valley rafters?

Answer 32

They run from an inside corner at the plates to a supporting valley

Question 33

When drawing a roof plan for an equal slope, intersecting roof, at what angle to the wall plates are the valley rafters drawn?

Answer 33

45°

Question 34

On an equal slope intersecting roof which ridge will be the highest above the plates?

Answer 34

The roof with the wider span

Question 35

Which one of the following numbered rafters is a valley jack rafter?

Answer 35

17

Question 36

Which one of the following numbered rafters is a supported valley rafter?

Answer 36

11

Question 37

Which one of the following numbered rafters is a hip-valley jack rafter?

Answer 37

15

Question 38

Which one of the following numbered rafters is a valley cripple jack?

Answer 38

14

Question 39

What is the first thing to layout on the top plates when framing a roof?

Answer 39

any openings in the ceiling

Question 40

What must be taken into account when calculating the length of ceiling joists?

Answer 40

the lap length or size of flush beam and position of bearing walls must be taken into account

Question 41

What are the shortenings for jack rafters framed to the hip or valley?

Answer 41

one-half the diagonal thickness of the hip or valley

Question 42

Which of the following rafters has the same theory length as the supporting valley rafter?

Answer 42

major hip rafter

Question 43

Where is the cutting line for the plumb cut of the bird’s mouth on a valley rafter located?

Answer 43

one-half the thickness of stock toward the tail

Question 44

What are the numbers to use on the framing square for the bevel cut of the sheathing to fit the valley or hip?

Answer 44

length per unit of run for the common and the unit of rise

Question 45

What is required for sheathing to fit over the top of the valley rafters?

Answer 45

the top of the supporting valley from the intersection of the valleys to the ridge must be backed off (bevelled)

Question 46

What is the shortening adjustment for the supported valley rafter at the top?

Answer 46

one-half the thickness of the supporting valley

Question 47

Which of the following statements is true of supporting valley rafters?

Answer 47

They run from the inside corner at the plate to the ridge

Question 48

What are the numbers to use on the framing square for the face cut of the sheathing to fit the valley or hip?

Answer 48

length per unit of run for the common and the unit of run

Question 49

What is the adjustment to the supporting valley rafter ridge cut?

Answer 49

one-half the diagonal thickness of the ridge board