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Carpenter 2nd Period > Roof Framing Systems > Flashcards

Flashcards in Roof Framing Systems Deck (69):
1

How many sloping surfaces does a gambrel roof have?

Four sloping surfaces

2

What is the name for the line, used to measure the length of a rafter, from the birds mouth plumb cut to the highest point on the "rise" of a roof?

Line length

3

What are other names for rake rafters?

Fly and barge rafters

4

Do intersecting roofs have valley rafters? T or F

T

5

Which box cornice has the soffit material attached directly to the underside of the rafter tails?

Sloping box

6

The minimum bearing length of a common rafter seat cut is ____.

38 mm (1-1/2")

7

What is wap?

Wood Above Plate. The amount of material remaining above the birdsmouth.

8

What is the building/roof span?

Horizontal measurement between the birdsmouth plumb cuts of two opposite common rafters.

9

What is the rafter run?

The horizontal distance from the centre of the ridge to the birdsmouth plumb cut.

10

What is rafter rise?

The vertical distance from the seat cut of the birdsmouth (top of cap plate) to the working point at the ridge.

11

What is rafter line length?

The calculated length of the rafter. It is the measurement taken from the working point at the ridge to the birdsmouth plumb cut.

12

What is overhang/projection?

The horizontal measurement from the face of the wall to the outside of the fascia.

13

What is a cornice?

The assembly of rough framing and finished materials installed at the end of the rafters.

14

What purposes to cornices serve?

1. They add to the architectural look or style of the building.
2. Protect walls from the weather.
3. Provide venting to the attic.
4. Provide a location to fasten eavestroughing.

15

What are the 3 styles of cornices?

Close
Open
Boxed or closed

16

Where are close cornices often used?

On roofs with no rafter overhang.

17

Close cornice: on roofs with no rafter over hang, what are the ends of rafters finished off with?

Frieze board.

18

What is a frieze board?

To make the transition from the exterior wall finish to the roof shingles.

19

Why are the top and bottom edge of the frieze board bevelled?

The top edge is bevelled to fit tight under the roof sheathing and the bottom edge may be rabbeted to receive the wall finish.

20

What is an open cornice?

An open cornice has rafter tails that extend beyond the wall, but no soffit is used to close off their undersides. The underside of the roof sheathing is exposed outside of the wall line; therefore, tongue and groove boards or paintable plywood sheathing should be used at this point.

21

What is used at the wall line of an open cornice?

Frieze boards and blocking between the rafter or truss tails which closes off the attic space.

22

Close and Open cornices usually provide eave protection.

False. They do not provide eave ventilation.

23

Close and Open cornices usually provide eave protection.

False. They do not provide eave ventilation.

24

Why are box cornices also called closed cornices?

Because the underside of the rafter tails is closed in with a soffit.

25

What are the two styles of box cornice?

Sloping box and flat box.

Note: both of these are usually vented at the eaves.

26

How is soffit material attached in a sloping box cornice?

The soffit material is attached directly to the underside of the rafter or truss tails. The wave and take (gable end) soffit follow the roof slope.

27

What is a flat box cornice?

The soffit material is level to the wall at 90 degrees. Older homes use lookout and ledgers. Newer homes use a special j-channel mounted to the wall.

Aluminum fascia is used to cover the rough wood fascia and helps hold the soffit in place.

28

What is a cornice return?

The cornice return makes the soffit transition from the flat under the eaves to the slope of the rake end.

29

What are some other names for a cornice return?

Pork chop, dogs ear, many others ha

30

What is the name of the framing members used to construct flat roofs?

Roof joists

31

What members are used to frame a projection on a flat roof?

Lookout joists.

32

How is the span measured for rafters on a shed or lean to roof?

From the inner face of the tall wall to the outer face of the short wall. Birdsmouth to birdsmouth

33

What are the main rafters used for gable roof framing called?

Common rafters

34

Hip rafters run 45 degrees to the wall plates and ridge. T or F

T

35

What is created on the roof surface where two roofs intersect at 90 degrees?

A valley

36

How many hip rafters are required to frame a Mansard roof?

8

37

What is the distinguishing feature of a Dutch hip roof?

Small gables framed at each end of the hip.

38

What is a dormer?

Dormers are small intersections built into roofs to provide an attractive feature or simply more liveable space in the attic.

39

Name the 3 locations where plumb cuts may be found on a rafter?

Ridge end
Birdsmouth
Fascia end

40

How is the projection of a rafter measured?

Horizontally from the face or the wall to the outer edge of the fascia.

41

What is the distinguishing feature of an open cornice?

Rafter tails that extend past the wall, but no soffit is used to close off the underside of the rafter tails.

42

Rafters require a minimum 38 mm bearing? Y or N

Y

43

You should maximize the amount of insulation space above the plate by laying out the minimum sized seat cut allowed by code. T or F

T

44

Does the ridge board provide support for the top of the common rafters, maintains rafter spacing and provides support for the roof sheathing at the ridge. T or F

T

45

Does the ridge board provide support for the top of the common rafters, maintains rafter spacing and provides support for the roof sheathing at the ridge. T or F

T

46

If the ridge is at least ___ thick, the rafters do not have to be placed directly opposite each other, but may be offset by their own thickness. T or F

T

47

Joints in a ridge board should occur on a rafter. T or F

T

48

When is a ridge board not required in a gable roof?

If the rafters are directly opposite each other. In this case, the opposing rafters must be tied together by a plywood gusset. Solid blocking is installed between the rafters to maintain oc spacing and provide backing for roof sheathing.

49

What does the slope gain factor represent?

The length gain along the slope for each unit of run.

50

The calculated line length of the centre gable stud is equal to the ____.

Rafter rise

51

What are two common types of gable rafter?

Dropped and Notched

52

If a single top plate is used the rafters must fall within __ mm of the studs.

50 mm

53

With a notched gable rafter, the lookouts on flat may be spaced up to __ o.c. Because the gable rafters provide support for the roof sheathing.

1.2 m

54

What is the rafter span?

Edge of support to edge of support. The face of the ridge board to where the rafter touches the wall plate.

55

Ceiling joists that help support part of the roof loads must be increased in depth by at least ___ mm

25mm

56

Lookouts should project in as far as they project out and be spaced to provide the edge support for the roof sheathing. T or F

T

57

Struts will extend from the rafters to a suitable bearing below. T or F

T

58

Hip roofs have 4 sloping surfaces. T or F

T

59

Hip and Valley rafters must be ____ greater in depth than common rafters and not less than 38 mm thick.

50 mm (2")

60

What kind of cut will be needed for the top cut of the centre gable stud of a gable roof if a 38x89 ridge board is used?

Square

61

What is one name commonly used for the framework needed for the gable overhang?

Ladder

62

If you choose not to drop the hip what will you have to do?

Backing the top edges of the hip

63

What is the name for the short walls built around the perimeter of the building?

Parapet

64

What members are required to frame a projection on a flat roof?

Lookout joists

65

What is the minimum length of the horizontal cut for a birdsmouth?

38 mm (1-1/2")

66

What must be done to a gable stud in order to fit it under a gable rafter?

What must be done to a gable stud in order to fit it under a gable rafter?

67

What are two types of gable rafters?

Notched gable rafter and dropped gable rafter

68

When framing a dropped gable, the gable lookouts provide support for the rake rafter. What other purpose do they serve?

backing for soffit material

69

What is meant by the term "Rafter Span" or the span of a common rafter?

face of support to face of support.