The weight of the roof will create pressure and then the hangers may pull away from their beam causing the walls on the exterior to come outwards to cause a visibly sagging roof line on the top of your roof.
How to repair a sagging roof line.
Sagging rafters can lead to serious problems with the entire roofing system.
If you notice that there is a visible dip in your roof chances are you have a problem with one or several rafters and you may soon be facing more issues like water leaks bowed out walls or your roof caving in on you.
After that use a piece of lumbar strapping to keep the plywood in place until you can get a roofing repair expert to fix it.
Push up on the plywood until the foam is touching the underside of the roof decking.
In some cases roof sagging problems are not caused by framing issues.
Step 1 the first step is to the basement first.
If that s what you re dealing with regarding your home take these steps to ensure your rafter or truss gets fixed properly.
In many cases you ll need to fix sagging trusses or rafters to repair your roof.
This is the easiest problem to repair.
You ll need a steel l channel to get your rafter or truss back into shape.
You will need to remove the shingles and the old decking however which means there will be an exposed hole in the roof.
This article describes a diy repair project using a site built spreader to straighten sagged roof rafters and decking.
Roof rafter decking sagging.
When considering what to do about sags in a roof start by noticing if the sag is in sheathing between rafters page top photo0 or sagging along the length of the rafters.
If the line does not continually.
If the sagging roof is due to rotting or warping roof decking the repair will be much easier.
How to fix sagging roof trusses or rafters.
This may be problematic in winter months but allowing the roof to continue to sag can lead to greater problems such as a cave in.
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.
Rotten or saturated sheathing can also cause roof lines to sag.