Underneath the basics flat roofs are usually constructed with a ceiling nailed to joists which support a deck usually wood in residential construction a vapor barrier insulation and a roof board.
Flat roof patio framing.
The roofing material is more traditional such as shingles.
When framing a flat roof you will need to create a slight incline.
In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.
Building a deck over a flat roof is very similar to building a deck over a concrete patio.
Here the rubber roof will need to run up the walls and glue to the sheathing.
These patio covers tend to look like an extension of the home s main structure.
The figures are based on quality materials.
First you must make sure the roof is strong enough to support 55 lbs per square foot.
Put a cement footing at each corner of the intended patio roof space and attach anchors to each footing.
When you are building a patio cover off of an existing roof or wall you must take all of your measurements from the point at which the patio roof will attach to the existing structure not the outside of the slab.
On two sides the roof abuts a parapet a short wall common around flat roofs as well as a wall for the third floor.
You can do this with a foam layer that exactly fits your roof.
The existing slab can vary considerably throwing off crucial measurements.
This is a completion video of a flat roof framing.
From there the flat roof system you choose will determine the materials you apply.
Flat roofs are always built at a slight incline at least 1 8 inch per foot.
These decks are often referred to as floating as they are not secured in place as a stand alone structure.
Some roofs actually slope in several directions ensuring optimal water runoff.
For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.
Patio cover plans building.
These traditionally styled roofs are made of wood and feature large supportive beams.
The tables below give maximum spans for rafters and beams.
To keep water from pooling at these inside corners tom rips 2x4s lengthwise on a 45 degree bevel with a table saw.
This will help you create a flat roof framing plan.
This is a completion video of a flat roof framing.