Flat roofs are renown for their waterproofing problems and problematic leaks, the nature of the design makes it very hard to drain water if there's been a downpour, and if high quality materials and good craftsmanship aren't used to build and repair leaks you'll set yourself up for further problems down the line. Although flat roofs can bring a certain life sentence with them and cause costly repair jobs, there's no reason that you can't have many a maintenance free year if waterproofing issues have been dealt with to keep water off, and find a way for it to drain off your roof effectively. If you're trying to find a solution to repair your flat roof waterproofing problems for good, or want to know more about repairing flat roofs, keep reading to find out how you can repair a flat roof leak successfully and effectively.

Locate The Leak

Before you can start any repair job you need to identify where the leak is coming from, the extent of the damage, and ultimately how you can fix it from there. Flat roofs are built up from many layers including roofing felt, tar and even rubber membrane. More times than not, the damage has occurred to the roofing felt which is easy to spot, you'll usually find leaks where this has been damaged.

Once you've located the leak and assessed the damage, check for any excess water from the leak and start by mopping this up and drying the area where possible. We would also recommend carrying out this job when there has been a few dry days in succession to allow the roofing felt to adequately dry out.

Repairing The Flat Roof Leak 

Small roofing repair jobs can be carried out by yourself if there isn't much damage, however if you feel like it is out of your depth or requires a more detailed eye it should be directed at a professional, we would especially recommend this if you're planning on staying in your current house for the foreseeable future. Different type of leaks and damages require different repairs so it's worth bearing this in mind whilst reading our guide. One of the most common repair jobs for a flat roof leak is blisters which is what we will talk you through today.


Blisters happen in small areas on a flat roof, the good news being that the whole roof doesn't need to be repaired when this happens. Blisters occur on the surface when moisture builds up in the roofing material. To fix this problem, use a utility knife to cut the blister down the middle, take extra care that you don't cut the further roofing material underneath as this will cause you further issues. Continue to cut around the blisters edges and place your thumbs at the edges of the blister. Apply pressure to the area and move thumbs towards the centre to squeeze out the excess water that it's holding. Mop up the excess water with a rag or towel and dry the areas as best as you can.

Now that the blister is free from water, apply a large amount of roof cement on the lower edges of the loose felt and press down on the blister. Seal the blister by nailing each edge of the slit closed by using galvanised roofing nails.

Other issues to look out for when fixing a leaking roof are condensation issues and roofing felt that needs removing. Once you understand what you're looking for it will make your life as a flat roof homeowner a lot easier and keep your mind at ease throughout the year. Even if you've had a free run of leaking problems, as a general rule of thumb homeowners should check over their flat roof twice a year to look for signs of weaknesses and potential issues that could get worse in a few months time. If you're looking to complete a repair job on a flat roof, please take a look at our flat roofs section of products for everything you need for a new build or repair job. To keep up to date with our blogs in the future make sure you're following us on: FacebookTwitter and Google +.



Post By Nicole Sage