The house is only 5 years old. We just purchased it and it passed inspection. A roofer came out and said the whole roof would need replacing because the OSB is coming loose form the rafters. We don't have leaking yet. Is there anyway we can fix this without putting on a whole new roof?
Sarah ~ Alabaster, Alabama
Sarah, if the OSB sheathing on your home's roof is separating from the rafters, then water infiltration problems are bound to occur, unless the problem is fixed. Without thoroughly inspecting your home, it would be difficult to determine what is causing the OSB panels to pull away from the rafters, but obviously the staples that were used to fasten the panels to the rafters are not adequate. The minimum fastening requirements supplied by most OSB manufacturers call for 8d ring shank nails, or 10d common nails, to be set every six inches around the panel's perimeter, and every 12 inches in the panel's intermediate field. Although there may be building codes in some areas that allow for certain types of staples to be used for fastening roof sheathing, I don't know of anyone that recommends it.
Short of replacing your entire roof, this problem could be difficult to fix. If the OSB panels are separating from the roof rafters in only a few places, then some construction glue may offer a temporary solution. A few well-placed screws, hidden under the roof shingles, may help to pull the roof sheathing tight against the rafters while the glue sets. Keep in mind though, this is not an acceptable solution if the problem is wide spread.
Aside from fixing the problem, it is important that you also determine the cause of the problem. It would be in your best interest to have several different contractors who work in the Alabaster area inspect your home's roof, as well as the underlying attic space, and offer some opinions as to what is causing the OSB sheathing to pull away from the rafters. A poorly vented attic might be causing moisture to condense on the underside of the OSB panels, which could be causing the panels to warp and lift away from the rafters. If this is the case, then a adequate attic vent system will need to be installed as part of your overall solution.