Roof Design and Framing

Question 1

What are the 3 types of roofs?

Answer 1

1. Pitched roof
2. Shed roof
3. Flat roof

Question 2

What is the rise and run of a conventional slope?

Answer 2

4 in 12 and up

Question 3

What is the rise and run of a low slope?

Answer 3

2 in 12 to 4 in 12

Question 4

What is the rise and run of a flat slope?

Answer 4

0 in 12 to 1 in 12

Question 5

Name the components of the anatomy of a common rafter.

Answer 5

1. Ridge Board
2. Collar Tie
3. Ceiling Joist
4. Double Top Plates
5. Wall Stud
6. Common Rafter
7. Plumb Cut
8. Tail Cut
9. Birdsmouth Cut

Question 6

True or False. In a slope ( Rise - Run ), the run is always 12.

Answer 6

True.

Question 7

True or False. Roofs are not measured in degrees.

Answer 7

True.

Question 8

Name the 7 types of roofs.

Answer 8

1. Gable
2. Hip
3. Shed
4. Flat
5. Gambrel
6. Mansard
7. A-Frame

Question 9

Define “Hip Roof”

Answer 9

It is a roof with 4 sloping sides that meet at a ridge board.

Question 10

What are the 5 components of framing for a hip roof?

Answer 10

• Common Rafter
• Hip Jack Rafter
• Hip Rafter
• Ridge Board
• Wall Plate

Question 11

True or False. Overhangs are a method of water management.

Answer 11

True. Overhangs help keep water away from the walls.

Question 12

What are the 4 components of framing for a flat roof?

Answer 12

• Common joists
• Double trimmer
• Lookout
• Header

Question 13

What is particularly cost-efficient about gambrel roofs?

Answer 13

A gambrel can create a 2nd story within the roof. Roofing materials are cheaper than envelope materials.

Question 14

What are overhangs used for?

Answer 14

• Block the summer sun
• Lets in the winter sun
• Keeps water away from walls

However, they are not used in dry climates.

Question 15

What is a “Gable End”?

Answer 15

also known as Eave; the extension of a gable roof beyond the end wall.

Question 16

What is a bird’s mouth?

Answer 16

It is a right-angled notch cut on the underside of a rafter to fit over a wall.

Question 17

What is the principal difference between a roof rafter and a roof joist?

Answer 17

Roof rafter supports loads of a pitched roof, whereas roof joists support loads of a flat roof.

Question 18

In what situation does a ceiling joist need to be calculated like a floor joist?

Answer 18

A ceiling joist needs to be calculated like a floor joist when the roof is an attic, where live and dead load from the occupants and the roof need to be supported.

Question 19

True or False. A bird’s mouth cut in a rafter is made near the eave.

Answer 19

True.

Question 20

In the building industry, the slope of a roof is generally expressed in…
a. degrees
b. rise to run ratio
c. radians
d. both a and b

Answer 20

b. rise to run ratio

Question 21

The cornice forms the connection between the __________ and the ________ of the house.

Answer 21

1. Roof
2. Sidewalls

Question 22

What are the 3 requirements to ceiling joists design in a roof?

Answer 22

1. Load to be supported ( How much snow is projected to fall )
2. Span of ceiling joists
3. Spacing of joists

Question 23

Name some of the supports a ceiling joist might use/need.

Answer 23

• Attic Knee Walls
• Collar Ties ( for slope 4 in 12, located at 1/3 )

Question 24

True or False. A ceiling joist can act as a tie for an exterior wall.

Answer 24

True.

Question 25

There are 2 types of dormer windows. Name them.

Answer 25

1. Gable 2. Shed

Question 26

What is the space that is planned between the framing and the brick/stone of the chimney?

Answer 26

2"

Question 27

In a __________ roof, if the rake end width exceeds _____ inches, we must use cantilever proportions for the lookouts.

Answer 27

1. Gable 2. 12

Question 28

True or False. Hip roofs have rake ends.

Answer 28

False.

Question 29

Define "Cornice"

Answer 29

The connection between the roof and the sidewalls of the building. ( Connection between roof and wall )

Question 30

Define "Eave"

Answer 30

also known as Cornice; it is the horizontal edge at the low end of a sloping roof.

Question 31

Name the 3 types of roof openings.

Answer 31

- Dormer - Skylight - Chimney

Question 32

What is the difference between a Gable Dormer and a Shed Dormer?

Answer 32

Gable Dormer: - Vertical Glass - Own Roof - Own Walls - Sits on a trimmer Shed Dormer: - Shed Dormer Rafter - Double Rafters - Exterior Wall Below ( + Weight transfers, lined up with wall to transfer loads )

Question 33

Name the 2 types of skylights.

Answer 33

1. Curb Mount 2. Framed-in-place

Question 34

For a skylight, how is the glazing installed?

Answer 34

Parallel to the roof slope. ( + 8 inch curve on a flat roof )

Question 35

In the case of chimneys, what methods are used to prevent the passage of water?

Answer 35

- Cap flashing - Step flashing

Question 36

To prevent build-up ( snow, leaves, branches, etc. ) what is installed centered on the backside of the chimney?

Answer 36

Saddle.

Question 37

How much space should be leave around the chimney?

Answer 37

2"

Question 38

Define "Underlayment"

Answer 38

It is a weather-resistant material for covering and protecting a roof deck before shingles are applied.

Question 39

What is underlayment?

Answer 39

Roofing underlayment is what lies between the shingles and the roof sheathing, or roof deck, which is typically either plywood or OSB. It is installed directly on the roof deck and provides a secondary layer of protection from the elements, including rain, snow, and wind.

Question 40

What is the purpose of underlayment?

Answer 40

It is to provide a second layer of protection located between the roof shingles and the roof deck. It is a waterproofing product.

Question 41

What are the 4 characteristics underlayment must have?

Answer 41

1. Industry-Leading Walkability 2. Grip 3. Trusted Dupont Tyvek Quality 4. Easy to Chalk

Question 42

What is "Ice Damming"?

Answer 42

An ice dam is an ice build-up on the eaves of sloped roofs.

Question 43

What causes ice damming?

Answer 43

Ice damming occurs when heat from the house heats the snow on a sloped roof and then melts the snow on the roof for it to reach the eave to freeze there.

Question 44

How to prevent ice damming?

Answer 44

Better insulation.

Question 45

What method is used to protect roof valleys from snow/water accumulation?

Answer 45

An ice + water shield and metal valley flashing are installed.

Question 46

Name the different types of roofing materials.

Answer 46

- Asphalt Shingles - Metal Roofing - Clay Tile - Cedar Shakes/Shingles For flat roofs: - Built-up roofing - Membrane roofing

Question 47

What are the 4 requirements when choosing roofing materials?

Answer 47

- Longevity - Water proofing - Fire resistance - Contributing to overall aesthetic design

Question 48

At how many inches should the end roll of an underlayment overlap?

Answer 48

4"

Question 49

True or False. Poor attic ventilation can ruin your insulation, destroy your shingles, and potentially raise your energy bills.

Answer 49

True.

Question 50

What are the ventilation requirements?

Answer 50

- Keep attic cool - Air must come in through the soffit vent - Air must come out through the ridge vent

Question 51

Ventilation: Low Slope 0-2:12 Conventional Slope 4:12 +

Answer 51

Low Slope: 1/150th Conventional Slope: 1/300th

Question 52

What are the causes of shingle deterioration?

Answer 52

- UV rays - Heat ( Thermal shock ) - Intense winds - Rain, snow, hail, ice, etc. - Trees

Question 53

Name the 3 types of roof valleys.

Answer 53

- Open valley - Closed valley - Woven valley

Question 54

What is a roof valley?

Answer 54

It is when two roof slopes come together.

Question 55

True or False. Wood shingles and shakes cannot be installed on a roof less than a 4-in-12 slope.

Answer 55

True.

Question 56

Name the 5 types of materials for metal roofing.

Answer 56

1. Copper 2. Aluminum 3. Stainless steel 4. Galvanized steel 5. Painted steel

Question 57

True or False. Metal roofing cannot be installed on flat roofs.

Answer 57

True.

Question 58

What are the 3 methods associated with membrane roofing?

Answer 58

1. Fully adhered 2. Mechanically fastened 3. Loosely ballasted

Question 59

What are the 5 types of membrane roofing?

Answer 59

1. PVC 2. Modified Bitumen 3. EPDM 4. Rubber 5. TPO

Question 60

Name the disadvantages of using roof trusses.

Answer 60

- Roof trusses leave no room for an attic space, due to their web - Roof trusses have a tendency to buckle/warp, which could affect the structural integrity of a building.

Question 61

Name the advantages of using roof trusses.

Answer 61

- Roof trusses are pre-fabricated, which allows for a more cost-efficient installation. They don't require any preparation in order to be used effectively.

Question 62

Name the 5 different types of trusses.

Answer 62

- King Post Truss - Howe Truss - Fink or W Truss - Scissor Truss - Mono Pitch Truss

Question 63

Other than specifying the pitch, span, and overhang detail, what else must a designer specify to the truss manufacturer?

Answer 63

Raised heel

Question 64

Why are the roof valleys seen as a critical area in roof construction?

Answer 64

The intersecting roof panes create a non-continuous area on the roof, which leaves that area prone to snow and water accumulation.

Question 65

The material placed directly under the roof shingle is known as... a. Sheathing b. Underlayment c. Air Barrier d. Insulation

Answer 65

b. Underlayment

Question 66

What is the purpose of using a self-adhered membrane at the eave of a pitched roof?

Answer 66

To serve as a snow/water shield in preventing ice damming.

Question 67

Name 1 of the causes of ice buildup at the eave end of a roof.

Answer 67

Poor Insulation.

Question 68

What is the purpose of a baffle or channel?

Answer 68

To serve as a passage of ventilation in a roof space.

Question 69

What are the factors used for a low/conventional slope of an insulated ceiling area?

Answer 69

Low Slope: 1/150th Conventional Slope: 1/300th

Question 70

Name examples of vents:

Answer 70

- Turbine - Maximum vent - Flat roof vent