If a roof dips in between rafters or trusses it s probably because the sheathing is too thin for the span.
Old house sagging roof.
A real problem in old houses maxfield says is multiple layers of roofing.
A sagging roof line may original from the ceiling s horizontal rafters.
1 2 inch thick angle iron.
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.
Sagging rafters can lead to serious problems with the entire roofing system.
Occasionally a house wasn t engineered properly for the type of roof that has been applied.
When the framing of the roof is put together quite frequently two of the ceiling rafters will be fixed together as this will create a much longer span.
Remedies for a sagging roof there are a number of remedies for traditional rafter style roof frames depending on the problem and its severity.
You can simply have the old sheathing replaced with better material when it s time for new roofing.
Properly built the roof of a house should be tied to the walls and the walls tied to the foundation so that the structure has a continuous load transfer from top to bottom with all elements well connected.
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.
If the framing is sound and problems are not found elsewhere but the roof still sags the problem might have originated because of poor installation of the plywood sheathing or shingles.
They just had rafters and one could be broken or sagging 5.
Use instructions from my page how to fix a sagging floor before you continue trying to fix the roof sagging issue.
Typically they are lapped and then toe nailed together in its center so that the correct length can be achieved.
So what happens with those elements is that you get more sagging and delamination of the roof sheathing.
You will need to remove the shingles and the old decking however which means there will be an exposed hole in the roof.
And in a 30 year old house you tend to not have very much ventilation.
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.
Typically the roof sheathing is about three eighths of an inch thick.
The old roof could have the slightest dip not easily perceptible.
Often the framing can be bolstered and beefed up internally but if the roofing material needs replacement anyway it may be best to tear off.
The first step is to the basement first.
If the sagging roof is due to rotting or warping roof decking the repair will be much easier.
Houses built before the 60s didn t have trusses maxfield says.
Roof design should provide wind resistance most old homes and many not so old homes simply are not built to take extremely strong wind.
Cracked rafters and trusses can cause sagging.
