Roof Structure
Last updated
Was this helpful?
Last updated
Was this helpful?
The roof is designed with a steep 45 degree (12:12) pitch to shed water and debris quickly so it will last longer. It has long overhangs to help keep the siding dry.
Wait to start the roof until you have a few dry days to work on it. It will be hard to cover until at least the roof sheathing is up because of wind. Precut the rafters and assemble the gables in advance. Now that the shed is enclosed, you can store the supplies for the roof inside. To help with organization we recommend building a simple lumber rack to accommodate the larger materials.
Cut the 2x4x8s to size using the Battery Powered Handheld Circular Saw and install them using the Battery Powered Electric Nail Gun.
Raised Top Plate
3"
24" on center
38' (19 Nails)
Cut, then assemble the gables on a flat surface. Cut a forty five degree edge onto the end of a spare 2x4x8. Stand up a gable and nail it to the joist below. Have someone Level the gable while someone else attaches the notched 2x4 to the center beam and a floor joist to keep it from tipping until the rafters and roof sheathing are installed.
Plate to Stud
End Nail
3.5"
2 nails
38 (76 Nails)
Cut the 2x6x12 rafters to size using the dimensions provided (C.03A). Make sure to cut notches in four of the rafters for the outriggers to sit into (C.03C). To remove the notches, adjust the Battery Powered Handheld Circular Saw to the depth required and cut multiple grooves until it is easy to use a Chisel and Hammer to remove the excess.
Pre-assemble three of the rafters, by connecting to the outriggers, with the overhang blocking (C.03D) before lifting them into place. Nail the rafter bottoms into the raised top plate and nail up from under the gable to secure the center rafter. Repeat for all four corners. See Rafter section for fastening.
Rafter to Outriggers
End Nail
3.5"
2 nails
28 (56 Nails)
Outriggers to Center Rafter
Face Nail
3.5"
2 nails
28 (56 Nails)
Rafter to Blocking
End Nail
3.5"
2 nails
28 (56 Nails)
Total
168 Nails
Next, run a String Line with a String Line Level east to west to determine a straight ridge line. Because of the length of the ridge beam, it is built in two pieces. Cut the 1x10x8 beam to size (C.04) and measure out and mark where the last two rafters should sit. Install the ridge beam by placing it on a gable and nailing two additional rafters at the end in place. Make sure the ridge beam stays true to your line to keep your roof from being warped. Nail the ridge beam to the rafters that are supported by the outriggers. Repeat for other side.
For additional support during construction, add Connecting Plates to the ridge beam joint.
Install the remaining rafters using the provided nailing schedule. Attach Hurricane Ties using Hurricane Tie Screws where the rafters meet the raised top plate using a Battery Powered Impact Driver.
Rafter to plate, toe nail
3.5"
2
32
64
Rafter to ridge, toe nail
3.5"
4
32
128
Total
192
Install collar ties to help prevent the rafters from coming apart at the top.
IRC Table 602.3(1)Collar tie to rafter, face nail
3"
3 nails on each side
6 connections (9 Nails)
Roof sheathing must be at least 5/8 inches thick (IRC TABLE R803.1)
Installing the 4x8 19/32" roof sheathing is the most laborious part of this design. Make sure to have at least two additional people helping you. Build simple slides out of four 2x6x12’s help you guide the sheathing up to the roof. Make the slides by attaching 2 of the boards together at the edges with 3.5" nails to make an angle and tacking them to the rafters ends with 2.5" nails driven at an angle. Notch a square corner out of a spare 2x4 to use as a pushing stick. Have one or two people lift the plywood up to the 2 people on the roof. Have one person on the roof tack the plywood into place using the nail gun once you confirm it is square to the bottom of the rafters.
Never have anyone stand under or in the slide in case someone on the roof loses their grip. Never have anyone reach out over the edge of the roof to grab a piece of sheathing. A good setup shouldn't require comprising safety.
Install H-Clips between the panels to add spacing between the panels so they can expand. Plywood is staggered for strength. Finish the nailing schedule for each piece before continuing to the next. Start with installing the bottom pieces before the top.
It may be difficult to reach across far enough to nail each piece in completely. In this case secure each piece as much as possible and make a note to finish the nailing schedule with a ladder once you're done.
To find the nailing locations, run a Plumb Bob Chalk Line down from each rafter and across the sheathing.
IRC TABLE R602.3(1)24' edge length for each 4x8 = 48 nails per sheet
Two 8' center lengths for each 4x8 = 16 nails per sheet
Edges on Studs
2.5"
Every 6" on center
12 sheets (576 Nails)
Center on Studs
2.5"
Every 12" on center
12 sheets (192 Nails)
Total
768 Nails
Ladder safety is extremely important, especially with a roof of this slope. You'll need to use the 24' Extension Ladder at an angle of one foot back for every four feet of height. Attach the ladder at the top to the sheathing or rafters using a Ladder Lock to help prevent side to side movement. You'll need a second 8 ft Straight Ladder to rest on the roof itself with 2 Ladder Hooks with Wheels attached. The wheels help you get the ladder up the roof until you can flip it over the ridge. Watch ladder safety videos and makes sure you're knowledgeable and comfortable before starting.
This is a good time to figure out how to cover the structure with the Tarp so the shed is protected from rain and you can take a break while finishing the gables. We wrapped a tarp over the roof and under the rake overhangs, tying off to the overhang blocking. Until we had the gable felt installed, we tied another tarp off starting with a corner under the ridge overhang and down to the eaves.
24' edge length for each 4x8 = 48 nails per sheet
Two 8' center lengths for each 4x8 = 16 nails per sheet
Edges on Studs
2 or 2.5"
Every 6" on center
4 sheets (192 Nails)
Center on Studs
2 or 2.5"
Every 12" on center
4 sheets (64 Nails)
Total
256 Nails
Attach
1 1/4" Cap Nails
Every 6'
28 Nails
Installing the Roof Felt can be tricky because of the angle of the roof. The roll has a tendency to slip down to roof. We gerry-rigged a tool to keep the roll at the right height by screwing a Dowel to a horizontal stake at the bottom inserting it through the roll and then screwing a vertical stake at the top. This allowed us to slide the roll across the entire roof. We adjusted the tool for the higher roll, It also makes sense to precut sections for the roof length to reduce the roll weight.
1 1/4" Cap Nails
Every 6'
30 Nails
Cut an 8 inch strip of Roof Felt to cover the ridge beam. This will make the structure water proof enough for you to no longer have to use a tarp as cover. Nail it down with Cap nails as it will be prone to fly off in heavy wind. You'll remove this piece once you're ready to install the ridge cap for the roofing.
10.96
Ladder Lock
39.39
8' Straight Ladder
86.22
2 Ladder Hooks with Wheel
45.50
Total
182.07
Measuring Tape
Foundation
Battery Powered Handheld Circular Saw
Foundation
Battery Powered Electric Nail Gun
Foundation
4' Level
Foundation
Speed Square
Foundation
Carpenter's Pencil
Foundation
Hammer
Foundation
String Line
Foundation
String Line Level
Foundation
Battery Powered Impact Driver
Foundation
Plumb Bob Chalk Line
Wall Structure
24' Extension Ladder
Wall Structure
Tarp
Foundation
Hammer Tacker
Wall Structure
Stakes
Foundation
2x4x8
Raised Top Plate
5
Gables
12
Overhang Blocking
6
Outriggers
10
Total
33
3.13
103.29
2x4x12
Gables
2
5.40
10.80
2x6x12
Rafters
32
Sheathing Slide
4
Total
36
8.03
289.08
1x10x8
Ridge Beam
1
18.36
1x10x12
Ridge Beam
1
27.46
Connecting Plates
Ridge Beam
2
.98
1.96
Hurricane Ties
Tie-down Rafters
26
.84
21.84
Hurricane Tie Screws
Tie-down Rafters
260
100 Pack
3
10.27
30.81
1x3x8
Collar Ties
3
4.45
13.35
4x8 5/8" (19/32)
Roof Sheathing
12
19.57
234.84
2.5" Interior Nails for your Nail Gun
Total in Pack
2000
38.7
H-Clips
Roof Sheathing
20
Total in Pack
50
8.11
4x8 3/8" (11/32) plywood
Gable Sheathing
6
12.53
75.18
Roof Felt
Rolls Needed
2
18.65
37.30
3/4" x 4' Dowel
2.98
Total
914.06
2.5" Interior Nails for nail gun
Roof Sheathing
768
Gable Sheathing
256
Total
1024
Left Over
276
Wall Structure
Needed
748
Remaining
1,252
3" Interior Nails for nail gun
Raised Top Plate
19
Collar Ties
9
Total
28
Left Over
952
Wall Structure
Remaining
924
3.5" Interior Nails for nail gun
Gables
76
Outriggers
168
Rafters
192
Total
376
Left Over
914
Wall Structure
Remaining
538
Metal Cap Nails
Gables
28
Roof
30
Total
58
Left Over
149
Wall Structure
Remaining
91
#30 216 Sq Ft Roll of Felt Paper
Gables
156 sqft
Roof
380 sqft
Total
536 sqft
Left Over
90 sqft
Wall Structure
Needed
446 sqft
