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How to Fix a Flat Roof Leak

Any roof can leak, but the flat roof provides a rather intense challenge. If you want to know how to fix a flat roof leak, then the first step is to find where the leak is occurring from an exterior standpoint. Just because the water dripping through the ceiling doesn’t mean that directly above that leak is where the water is coming in from the roof. Here’s what you’ll want to look for on the outside.

Where Are the Low Spots?

Flat roofs tend to be built with a number of layers of tar and felt. Although the roof is flat, it isn’t perfectly flat. As the building settles, there will be low spots that begin to develop. It is in these low spots where the greatest potential of leaking happens. Usually this is pretty easy to see once you get eyes on the problem. Remove any water that may still be present and allow the surface dry.

Do You Have Any Cracks?

Once the roof has dried, will want to make sure you brush away any debris that may be in potential leak area. As you are doing this, you will want to look or any cracks that might be in the felt of the roof. Will also be looking for places where the tar may have not sealed the roof properly. This usually is in the form of a blister within the tar.

Did You Find a Tar Blister?

If you found a blister, then take a sharp knife and slice it open right down the middle. You need to go to the full depth of the bubble. Remove the edges of the blister and then mop up any water that may be contained within the bubble. You may need to let the edges of the blister dry after this and some blisters may be so large that you need to propped the edges up.

Is It Too Cold or Too Wet to Dry the Roof?

In some climates, it can be virtually impossible to let the roof dry on its own. You can supply artificial heating methods to encourage the process. Propane torches or portable heaters will work, but make sure you take all appropriate safety measures so that you and your building stay safe.

Seal up the Roof Once you Have Eliminated the Issue.

Whether you have found a crack or a blister, once it has dried, it is important to seal it up. Use roof cement along the bottom edges of any loose felt first and firmly pressed down so that the roof becomes flat once again. Using galvanized nails, affix any loose layers so that you have a firm repair. Then cover the nails and the repair site with another layer of roof cement to prevent future leaks from occurring. A flat roof is sometimes a necessity. The good news is that you don’t have to live with a leaking roof, even if it is flat. Use the steps to repair your situation and you will know how to fix a flat roof leak.

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