Siding leaks appear in many shapes and forms. Water stained interiors are quite often the first indication to homeowners that they may have problems with a siding leak. As mentioned in our other articles ruling out ice dams is one of the first things you should do if you believe you have a siding leak. Many times roofing leaks can mimic siding leaks so we recommend keeping this in mind as you search for the cause of your leak.
There are a variety of siding materials such as cedar, vinyl and cement board and each has it’s own most likely cause of leaks. Take for instance cedar clapboard siding. As this natural wood ages it can warp, split and have knots that may come loose and even fall out over time. When looking for a leak with cedar clapboard siding you will want to first do a thorough inspection of the siding in the area of the leak. Look for obvious problems like loose or missing knots and dried out caulk. You will then want to look under the laps of each piece of siding where the pieces lap over each other. Sometimes a small split will develop which can only be seen upon close inspection. Check around the leak area and make sure all the wood corners and joints around windows and doors are sealed with a very good quality sealant. Once water is able to work it’s way behind the siding it can then end up in your finished living area. Many times with siding all that is required to fix a leak is a little high quality sealant.
Vinyl siding is a little different than wood siding when it comes to leaks. Wood siding is nailed tight and caulked tight at joints and end points. Vinyl siding is nailed loose and is captured at end points by receiving channels that allow for expansion and contraction of the siding. These receiving channels have flanges behind them to help direct water that may enter. As in wood siding a thorough inspection of the leak area is recommended. Pay special attention around windows and doors tops as these can provide entry points for water. Make sure all caulking is in good shape and replace any old caulking as needed with a very good high quality sealant.
Each year we receive calls to help diagnose and repair siding leaks that are occurring at siding and roof intersections such as where a garage roof meets the main body of the house and has siding installed on the wall above the roof. One of the first questions we ask is have you had your home resided is the past few years. If the answer is yes we then ask did they cover the roofs step flashing with anything before installing the new vinyl siding. When old siding is removed on a wall where there is roofing at the base you will see the roofs metal step flashing at the base of that wall usually about two inches up the walls face. Many siding companies will just install siding channel against this flashing and then proceed to install the new vinyl siding covering the rest of the flashing. Over the years we have seen many cases were this type of installation leaked during heavy rains. What was occurring was the water was being driven down the siding channel and jumping the roofs step flashing that was only up on the wall behind the siding two inches. Another problem that can occur is water flowing down the shaft of the nail used to hold the sidings channel and into the home. Our solution to the problem was to cover the roofs step flashing with fan fold insulation. Even if a homeowner elects not to install optional fan fold insulation under new siding we still recommend and install at least one band of this over the roofs step flashing. We feel this step alone has saved many homeowners the grief of a common siding leak down the road.
These are just a few common leaks that can occur with siding. Maryland Shingle Roofing and Siding Contractors can help with most all your siding needs. Please feel free to contact us if we can be of any assistance.
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