An Attic Leakage Inspection is designed to prevent water intrusion.The underside of the roof must be checked regularly for signs of past water leakage and, if the structure is checked during a rain, current water leakage. Water stains may show up on the sheathing or roof rafters, appearing as dark-streaked discolorations on the wood. In some homes, there is separate masonry chimney for the fireplace and a prefabricated chimney for the heating system. In this case, joints vulnerable to water leakage are those between the chimney and the roof and between the vent stacks and the roof. These joints should be inspected for leakage, though it is a relatively minor problem and can generally be corrected by sealing the joints with an asphalt cement.
Attic Leakage Inspection – Evidence of Water Intrusion
A leaking roof should be treated as an emergency because it can wreck a house in a very short period of time. To limit damage, attend any signs of a roof leak (water infiltration, stains, mold etc) immediately. Locate the leak from the inside and take steps to control the damage until a professional home inspection and repair.
The first place to look for a roof leak is directly above the leak in a ceiling or exterior wall. Use a flashlight to inspect the attic floor over the leak during a rain and look for ponded water, water stains, mold, wet insulation or other exposed insulation. Check the underside of the roof for wetness or mold around points of penetration (chimneys, plumbing vents), wherever different roof planes intersect and near dormers. Such symptoms might be an indication of holes in the flashing or faulty flashing installation.
If the leak is away from such locations, it might be an indication of a problem in the roofing material. Take measures from points inside that you can also locate from outside. Start by measuring down from a ridge and horizontally from the center of a valley or sidewall, or measure distances from a chimney to another point of penetration.
If you roof is attached to roof rafters as with cathedral ceilings, all you can do from the inside is take the measurements that will help you locate the leak externally, and attempt to control the damage internally.
Controlling the damage
Before dropping off in one or more places, water can travel on the underside of sheathing or down roof rafters. To control where it falls, tack a piece of string into the stream of water and let it hang into a bucket. The water will follow the string. To prevent the water from spreading across the top of the ceiling to other areas, poke or drill a home in your ceiling to let the water get through. This prevents the ceiling from becoming saturated, eliminating the chance of collapse.
Locate the leak from outside
Using any measurements or information noted indoors, make your initial outdoor observations from a ladder and/or using binoculars. Do not walk on a pitched roof during rain or if the roof is wet. Also, a wood roof is particularly dangerous.
Check for leaves and other debris slowing the natural downward flow of water. If there is snow on the roof, an ice dam may have formed at the roof’s lower edge, causing water to back up in overlapping layers of roofing materials. If you can reach it safely, simply remove the obstruction.
In addition, if you can safely get close enough, check the metal flashing for corrosion or open joints where they connect to a chimney or other roof penetration. You can temporarily patch metal flashing, but the only permanent solution is replacement. Generally, you can replace cracked or dried-out rubber gaskets on plumbing vents. Pay special attention to any areas already covered with black flashing cement, because these indicate locations of previously repaired leaks. Check for cracks or pinholes, which often occur as the material ages. As a temporary repair, apply flashing cement with a putty knife.
Also, if you can safely get close enough, check attachment points for any antenna, satellite dish or other object screwed or nailed into the roof. A dab or roof flashing in good condition should cover each fastener. Still, the best thing to do is to avoid mounting anything on the roof in the first place.
If you noticed from the inside that your leak is mid-roof, therefore not related to flashing, check for damaged or missing asphalt shingles, or, on wood roofs, look for cracked or badly cupped or warped shingles or shakes. Note that flat or nearly flat roofs typically require very close inspection to locate damaged or badly worn areas.