Roof Sheathing Problems

When water flows off the edge of your roof some of it clings to the underside of the shingles and dribbles toward the fascia.

Roof sheathing problems.

While you re in the attic scan the underside of the roof sheathing for any new signs of water staining since the last inspection as well as any soft or moist spots which tend to show up after a heavy rain. Buckling can occur if the wrong type of nails were used to connect the sheathing to the rafters. Waterlogged roofing materials and sheathing will bend and bow creating dips or making a ceiling take on a convex appearance. Condensation on the underside of foil backed osb can cause several problems.

The authors of the first paper cited a study in south carolina where the relative humidity in the attic was way too high in summer 80 to 100. If the walls are crooked the rafter tails will also be crooked. This is crucial because this building line will be a very noticeable when viewed from below. Eventually the fascia soffits and even the roof sheathing will rot.

The nails slip out of the sheathing and create small visible bumps on the surface of your roof. One of the most common signs that a roof s sheathing is damaged is a roof leak. You might find holes left over from a satellite dish or antenna mounting brackets or just about anything. The problem exists because nail sizes and spacing used to attach the sheathing to the roof s structural members rafters or trusses do not provide enough strength to keep the sheathing on during.

The importance of roof pitch photo by julian wass. Moisture can lead to mold which is both unhealthy to the occupants of the building and can rot the ceiling framing or wall assembly. A sagging ceiling is another clue that there are major problems with a roof s sheathing. Such leakage can lead to the development of mold and mildew within a home.

But where does the moisture come from. Tiny holes in shingles are sneaky because they can cause rot a leaky roof and other damage for years before you notice the obvious signs of a leak. If you have gutters but no gutter apron to stop the water it will wick behind the gutter. If these problems are widespread it s a sure sign that you need to call a roofer.

And exposed misplaced roofing repair nails should be pulled and the holes patched. In addition a leaking roof is more prone to collapse as well as the formation of large gaps and holes. Try to correct this problem. If the insulation becomes damp it will lose some of its insulating values.

Without proper air flow moisture can build up behind the home s exterior siding and supporting structures cannot dry out creating mold and deterioration problems. The osb got wet and rotted. Some houses with open cell spray foam installed on the underside of the osb roof sheathing have had moisture problems. A broken sagging rafter will also cause a dip in the roof s surface.

Faulty durability as home construction has evolved throughout the years we have seen sheathing methods change from boards to plywood to oriented strand board osb.