Roof Truss Issues

Repairing truss uplift problems if you re building a new house inspect your trusses.

Roof truss issues.

Arched roof trusses moving in response to moisture temperature variations across the truss can lift the building ceiling sufficiently to cause nail pops or actual tears at the ceiling wall juncture. Dry wood shrinks moist wood expands. Damaged or missing gusset plate it must be intact and free of corrosion. If the drywall can t move enough to accommodate the warp it cracks away from the wall.

The upper members of the. Roof truss uplift occurs when the bottom chord of the truss is exposed to significantly different moisture and or temperature conditions than the rest of the roof truss. These areas of the roof subjective to compressive forces oftentimes face roof support problems such as the truss members buckling or distort out of a plane and unless they are properly braced to hold them tight during erection the entire truss may warp up and distort out of a plane. This can lead to structural issues and occasionally the roof sagging.

Because the bottom chord of the truss is buried in heavy insulation it experiences different conditions than the top chord. A broken roof truss can cause many different problems. The good news is that the problem can be fixed fairly easily with a few materials a helper and diligent application of the steps below. Should a decision be made to modify a truss in order to raise the ceiling in an area allow more storage or move a stairway then it is wise to consult an engineer for assurances that there is no structural issues.

3 defective lumber sometimes a knot or check in the lumber of a truss is intact and appears structurally sound when the roof is installed but pops open later. They should not be nailed to a wall using 16 penny nails. If the truss is bad enough it can cause the sagging or collapse of a roof. Tim also revealed another common issue being that trusses are sometimes modified on site without approval which can affect the structural integrity of the roof and lead to major problems.

If you see nails they must be pulled and the special truss clips installed in their place. Roof truss uplift can be diagnosed as the cause of nail pops and cracks or separation between the ceiling and wall top. The construction concerns article dated february 13 2013 discusses the roof trusses of an 1840s grain elevator with a pitched roof shaped like a capital a. Resin dripping from the wood as in the photo below is ugly but not a structural defect.