If they are sound but just not properly supported from below you can guild a knee wall half way up the roof just like as if you wanted to make an attic room.
How to brace up a sagging roof.
Hang a plumb bob from the nail and mark the point where it touches the joist below the rafter using a.
Push up on the plywood until the foam is touching the underside of the roof decking.
Drill holes in angle iron.
Measure the length of one of your rafters and mark the rafter at its midpoint.
If these already exist nail a 2x4 to them directly under the 2x4 plate you nailed down before.
Next place your piece of plywood and styrofoam foam side up against the damaged roof decking.
Perhaps the sheathing is the problem with your sagging roof.
How to straighten sagging roof rafters.
Non foundational reasons for a sagging roof.
Two or more roofs on one structure spell trouble.
That s how to fix a sagging roof.
Be careful because you can push the roof right off of the wall below as you see where i drew an arrow in the lower right hand corner.
Here the roof has been pushed up nicely and we are ready to measure for a brace.
How to brace roof rafters from sagging.
In raising the roof i knew was going to have to reset the roof s flashing as it meets a sidewall of the house.
This is called undercutting.
If that is the case you need to.
Once you have established how much the roof sag needs to be jacked up lay a 2x4 plate across the ceiling joists and nail directly under the ridge of the roof.
You will need to get up into your attic and examine the roof carefully in order to discover the underlying cause.
Likewise a flood resulting from a broken water line or natural occurrences can compromise your roof eventually.
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.
The result is pooling water causing erosion of the soil meant to support the foundation.
Before you try this method you need to determine whether or not the sheathing that remains is strong.
Fixing a sagging roof by bolstering the beams replacing sheathing.
Now add collar ties from one side of the rafter to the other.
Brace 1 has been secured but will still allow some settling and adjusting between it and the next brace.
Tap a small nail into the side of the rafter at that point.
Things to consider with jack up a porch roof the prep.
So to begin i removed the existing counter flashing running about 5 courses up this was as easy as finding nails and prying.
Determine the extent of damage.
In most cases a sagging roof is caused either by a broken rafter or roof decking but in some more severe instances a damaged or sinking foundation can be the underlying cause of the problem.
