You should obtain a piece that measures 1 2 with sides that measure 4 in length and an overall length of the entire piece being a minimum of 2 feet.
How to take the sag out of a roof.
Push up on the plywood until the foam is touching the underside of the roof decking.
If the line does not continually follow the bottom of the beam and the bottom of the beam is below the line the beam is sagging.
Determine the extent of damage.
You can do this by guarding it using an angle iron piece.
How to straighten sagging roof rafters.
Next place your piece of plywood and styrofoam foam side up against the damaged roof decking.
Check the ceiling for sagging by attaching a string on one end of the beam and run it along the bottom edge of the beam.
Use instructions from my page how to fix a sagging floor before you continue trying to fix the roof sagging issue.
It may be necessary to tear up shingles to fix a sagging roof.
That s how to fix a sagging roof.
Drill holes in angle iron.
The first step is to the basement first.
The first step is to find out how many rafters are sagging and if anything else is damaged.
It is best to do all repairs from the top of the roof which means you will have to tear up shingles and other coverings as well as the roof decking in some cases.
It s ok to save your money sometimes that s what is diy is about but it s not money it also fun and more love to your project that s why i like diy always.