The source of most roof leaks is hard to find because it originates away from where the leak shows up. In order to find the source of a leak, follow a roofer’s advice and “think like water.”
Water typically comes in through worn, broken, or missing shingles; where nails have worked loose; or through corroded or poorly sealed roof flashing around vents, skylights, or chimneys or along the intersections of roof planes. Once water passes the roofing, it flows along the sheathing, roof rafters, or topside of ceilings until it finds a place to drip down—inevitably onto your favorite piece of furniture. Look for a roof leak during the day. Go into the attic with a bright flashlight; step only on secure framing members and never on the insulation or topside of the ceiling below—neither of these will support you! Start above the place where the drip has occurred and work your way uproof, looking for wetness along the framing members.
If the weather has been dry for a while, look for water marks, stains, or discolorations on the wood made by moisture. Then switch off the light and try to find a hole where daylight shows through the roof. (With a wood-shingle roof, you’ll see many such places, but while the overlapped shingles let light show through they shed water.) If it’s still raining, put a bucket under the leak in an area with proper support. Let the bucket collect the drips and fix the leak when the weather clears. You can also use a company like roofbuildhomeimprovements.co.uk to sort the leak for you, if you don’t have the tools
When installing shingles, make sure the nails are embedded securely into the felt and sheathing. Over time, the sun’s heat will cause the roof and shingles to expand, making the nails pop out of place and thus increasing the risk of a leak. Because the roof is sloped, make sure you layer the shingles from bottom to top, overlapping the top set with the bottom. This will ensure your roof is protected from all the weather elements.
Rent a nail gun. Most can be rented for about $20 a day. The gun usually comes with a measurement guide that can save a lot of time. The standard width between each row of shingles is 5 inches.
After cleaning the debris and reframing the roof, lay down a base (sheathing). Eight-foot, 1/2-inch-thick plywood is standard sheathing material. Measure the opening of the section of roof to be shingled, cut the plywood to size and nail to roof rafters. Stagger the sheathing in a brick pattern for extra strength. Do not place an entire 8-foot section of plywood onto roof. Such a long piece is structurally unstable in the middle. Continue to install in brick pattern, staggering the plywood seams until the open area is covered. Start by stapling the 6-inch starter strip at the bottom section of roof leaving a 1-inch overhang on the eave to ensure drainage into the gutters. Going from bottom up, lay and nail the remaining felt layers with a 2-inch overlap. Be sure to nail the tar strip on each felt layer to ensure maximum hold. Companies like roofbuildhomeimprovements.co.uk will always be on hand for good advice when repairing a roof.
Lay the first row of shingles starting at a bottom corner of the roof. Place a base row of shingles following the chalk lines on the felt and move upward in a pyramid shape. Use six nails per shingle to ensure maximum hold, and be sure to always nail on the tar strip. Continue working your way across and up the roof, following your initial pyramid base. If repairing a section of damaged roof, be sure you layer the existing shingles on top of the new. This will ensure a uniform and seamless look.