The first approach to achieving a strong durable struc ture involving economical use of materials is to follow a basic modular plan for layout and attachment of framing members.
Roof deck framing details.
First you must make sure the roof is strong enough to support 55 lbs per square foot.
You will need to attach the porch rafters to the house roof rafters and replace the roofing and flashing.
Wood construction data 1.
They are merely placed on top of another structure.
Cdx plywood glued and screwed to the framing.
When using purlins fabral recommends a maximum spacing of 24 on center note that 5v requires solid decking.
Position the square at the end of the rafter board with the tongue on your left and facing away from you.
Add the length of the overhang beyond this mark and.
Such methods use a 4 foot design module which governs a 16 inch spacing of joists studs rafters.
Fiber roof underlayment as a final substrate.
The roof sheathing is 3 4 in.
The roof deck should be properly flashed with a.
The roof deck surface should sloped away from the house a minimum 1 8 inch per foot so the water will drain and not pond the finished walking surface of the roof deck surface should be below the level of the interior floor by at least 1 1 2.
Measure form the top of this line down the board to determine the line length or length of the rafter less the ridge.
Rafters should be attached to the header beam using hurricane ties.
To create a smooth surface and to protect the bottom of the rubber roofing from any fasteners or rough edges on the plywood i installed 1 2 in.
These decks are often referred to as floating as they are not secured in place as a stand alone structure.
Kiln dried softwood is recommended for purlins or decking pine fir hemlock and spruce.
As with other decks guardrails must be a minimum of 36 inches high infill balusters less than 4 inches apart and the whole assembly strong enough to resist a 200 pound horizontal load or 20 pounds per linear foot depending on the local code.
Pullout values decrease if the fasteners protrude completely through the purlins.
Post and railing construction for rooftop decks.
Download free high quality cad drawings blocks and details of roof and deck insulation organized by masterformat.
If you are tying the shed roof into an existing roof on the house you will need to remove the shingles and sheathing to expose the roof framing.