Roof Framing Definition

Front 1

Direct proportion

Back 1

Two or more quantities increase or decrease on the same ratio

Front 2

Common rafter

Back 2

Extends perpendicular from ridge to cap plate

Front 3

Rafter run

Back 3

Centre of ridge to outside of outside wall

Front 4

Rafter span

Back 4

Face of support to face of support

Front 5

Rafter line length

Back 5

Sloped length from the centre of the ridge to the outside edge of the wall

Front 6

Rafter tail line length

Back 6

Length of the overhang or projection

Front 7

Total rafter line length

Back 7

Total length of the rafter run and the overhang run

Front 8

Shortenings

Back 8

Measured from the working point at the center of the ridge to the outside of the fascia

Front 9

Perpendicular shortenings

Back 9

Must be measured at 90 degrees to the working plumb line

Front 10

Diagonal shortenings

Back 10

Shootings are always done at a diagonal to other framing members

Front 11

Full diagonal shortenings

Back 11

All Hip or valley rafter outside the exterior walls will be full diagonal thickness

Front 12

Half diagonal

Back 12

All hip or valley shortening within the boundaries of the exterior wall

Front 13

Dropped/ backed rafter

Back 13

Hip rafter drops so it can sit lower in relation to the common rafter.

Front 14

Gable stud

Back 14

Placed directly under the stud,

Framed triangular shaped walls at a table roof

Front 15

Notched gable stud

Back 15

Notches cut into the top of gable look outs

Front 16

Dropped gable

Back 16

Lowered so gable lookouts can run over it

Front 17

Lookouts

Back 17

Support the rake rafter.

Project in as far as they project out. Spaced to provide the edge support for the roof sheathing

Front 18

Ladder systems

Back 18

Lookouts placed on edge rested on top of a dropped gable rafter, short gable end wall frames underneath them.

Front 19

Barge/ fly / verge rafter

Back 19

Also known as rake rafter

Front 20

Ridge board/ridge beam

Back 20

Maintains rafter spacing, provides roof sheathing at ridge

Front 21

Collar tie

Back 21

Horizontal members nailed to the sides of opposing pairs of rafters.

Placed upper third of total rise of roof

Front 22

Seat cut extension

Back 22

Extends out to end of the rafter

Front 23

Theoretical measuring line

Back 23

Runs parallel to the end of the rafter.

Intersect the corner of birds mouth and up to the working point at the ridge.

Front 24

Common difference

Back 24

1- hip Jack's become shorter by a consistent amount.

2- centre table stud working outside wall becomes shorter

Front 25

Hip rafter

Back 25

Runs diagonally 45 degrees from outside corner of the building to the ridge.

Hip roof requires four hip rafters

Front 26

Pin rafter / end common

Back 26

Runs 90 degrees connecting the plate and the ridge

Front 27

45 degree rule

Back 27

Only used for hip and valley rafters

Front 28

Gable end overhang framing

Back 28

Overhang is required at either end, special framing must be used to allow the roof to project past walls. Lookout rafters are used

Front 29

Short walls built around perimeter

Back 29

Front 30

Back 30

Lean-to roofs or flat roof

Front 31

Back 31

Gable roof

Front 32

Back 32

Hip roof. 45 degree angle to the wall and ridge

Front 33

Back 33

Intersecting roof, 90 degree angle. Valley is created

Front 34

Back 34

Gambrel roof. Also called barn roof

Four sloping surfaces, two sets rafters

Front 35

Back 35

Mansard roof, 8 sloping surfaces. 8 hip rafters

Front 36

Back 36

Dutch hip roof.

Combination of hip and gable roof

Front 37

Back 37

Butterfly roof

Inverted gable roof

Front 38

Back 38

Monitor roof

Combination of gable and shed roof.

Commerical or agricultural building

Front 39

Back 39

Dormers

Shed and gable dormers

Front 40

Intersecting roof

Back 40

Two or more roofs joined together

Front 41

Supporting valley

Back 41

Extends from the major roof ridge to the corner of the building intersection

Same line length as the hip

Front 42

Supported valley

Back 42

Extends from the supporting valley rafter to the corner of the building intersection.

Parallel to the minor hip rafter.

Same horizontal run as the minor hip, same line length

Front 43

Valley jack

Back 43

Runs 90 degrees to the ridge, extends from either major or minor ridge down to the valley.

Identical to the common rafter.

Front 44

Valley jack on minor roof

Back 44

Equal to its distance form the intersection of the supporting and supported valley rafter

Front 45

Longest Valley jack on major roof

Back 45

Find its distance from the corner at which the walls intersect.

Front 46

Valley cripple jack

Back 46

Runs from valley to valley.

Extend from the supporting valley to the supported valley.

Shortenings half the diagonal thickness of the valley rafter.

Opposite cheek cuts

Front 47

Hip-valley cripple jack

Back 47

Runs from hip to supporting valley.

Does not touch ridge or wall plate.

Can be seen as the middle section of a common rafter.

Equal to the offset of the minor roof

Front 48

Intersecting roof lines major

Gable

Back 48

Minor gable

Front 49

Major intersecting roof lines

Gable

Back 49

Minor hip

Front 50

Major intersecting roof lines

Hip

Back 50

Minor intersecting roof lines

Gable

Front 51

Major intersecting roof lines

Hip

Back 51

Minor intersecting roof lines

Hip

Front 52

What's the layout of the upper end of valley jack rafter

Back 52

Half the thickness of the ridge

Front 53

Layout of the lower end of the valley jack rafter

Back 53

Meets valley at 45 degree and a single cheek cut