A leaking flat roof is a common problem that can turn into serious damage if not fixed quickly. It can damage your ceiling, walls, and even your home’s structure.
Most flat roof leaks can be fixed easily with some basic tools and clear steps. Fixing the leak early can stop the damage and prevent expensive repairs.
In this guide, we have explained how to fix a leaking flat roof, which repairing materials to use depending on your roof type, and how to prevent future leaks.
How To Fix A Leaking Flat Roof?
Before you start the repair, check the roof carefully and make sure it’s safe to work on. Below are the steps you can follow to fix the leak properly on your own without professional help.
Step 1: Find the Leak Source
The first step is to look for the exact spot where the roof is leaking. This may not always be right above the wet patch on your ceiling. Water might travel from one spot to another before dripping down. Go up on the roof when it’s dry and look for cracks, holes, bubbles in the roofing material, or areas where water is pooling.
Also, check the flashing around vents, skylights, or chimneys, as these are common spots for leaks. If you can’t find the leak, read our detailed guidance on how to find a leak in your roof. After this, you can easily find the leaks.
Step 2: Gather Tools and Materials
Before you start fixing your flat roof, it’s important to gather all the tools and materials you’ll need. Having everything ready will make the repair process quicker, safer, and more effective.
| Tools | Materials |
| Ladder | Roofing sealant |
| Utility knife | Roof patch |
| Brush or roller | Roof adhesive or glue |
| Bucket or container | Roofing tape or flashing tape |
| Caulking gun (for sealant) | Tarp (for emergency cover) |
| Measuring tape | Cleaning solution (soapy water) |
| Safety gloves and goggles | Roofing nails or screws |
Step 3: Clean the Area
Once you’ve found the leak, clean the area around it so that repair materials will stick properly. You can use a stiff brush to remove dirt, dust, moss, or loose material from the roof surface.
If there is standing water, use a sponge or towel to soak it up. Make sure the area is dry before you move on to the next step. This will help the repair last longer and seal properly.
Step 4: Choose the Type of Material
The way you fix your flat roof depends on what kind of material it’s made from. There are different types of repair materials for flat roofs.
- For felt roofs with small cracks or holes, you can use roofing sealant, and for large damage, use a roofing felt patch.
- If your roof is made of EPDM rubber, you can use a rubber patch and adhesive.
- For fibreglass or GRP roofs, a resin repair kit is usually the best solution.
Step 5: Apply the Repairing Material
Now, you have to fix the leak using the repair material. For small cracks or holes, use a roofing sealant. Use a caulking gun or knife to spread the sealant over the holes. Then smooth it out evenly to make sure it is fully sealed.
If you’re using a felt patch, which is commonly used, press it firmly onto the area and make sure all edges are sealed tightly.
Always follow the product instructions, especially for drying time. Try not to rush this step because when everything dries properly, it helps the repair last much longer.
Step 6: Check Results
After the repair has dried fully, check your work to make sure everything is sealed well. Pour a small amount of water around the repaired area or wait for the next rainfall to see if the leak is really gone.
If it still leaks, you may have missed a spot, or the damage may be more serious. It might be time to get help from professional flat roofing services to fix the issue properly.
Emergency Flat Roof Leaking Repair
If you can’t fix the leaks right away, especially during heavy rain or a storm, you should take quick steps to stop the water from causing more damage. These are only temporary fixes, but they can help protect your home until you’re able to do proper repairs.
- The first thing you can do is cover the leaking part of the roof with a large waterproof tarp. Spread the tarp over the damaged area and secure it using nails, bricks, or anything heavy so the wind doesn’t blow it away. This will help keep most of the rainwater out.
- If the leak is small, you can also use special roofing tape or a quick patch. These products are made to stick to wet surfaces and seal small cracks for a short time. They’re not a long-term solution, but they can stop the leak until you get proper materials or help.
- You can also place a bucket or container under the dripping water inside the house to catch it. This will help protect your floors, carpets, and furniture from water damage. You can also put towels around the bucket in case any water splashes out.
These quick steps won’t fix the leak completely, but they can save you from bigger problems while you wait for better weather or help from a roofer.
How to Prevent Future Roof Leaks?
Preventing roof leaks before they start is always better than fixing them later. One of the best ways to protect your flat roof is by checking it regularly for any signs of damage or wear. Check your roof often for any cracks, bubbles, or worn-out areas.
Keeping the roof clean from leaves, dirt, and debris is also very important. Debris can block water drains, and causes water to pool on your roof. Standing water weakens the roof material and makes leaks more likely.
If you see small cracks and holes, fix them immediately. Use the right repair materials made for your specific roof type to make sure the surface stays waterproof and strong.
Also, make sure gutters and drains are clear and working properly. Blocked drainage can cause water to collect and damage your roof over time.
Conclusion
Fixing a leaking flat roof is easy by following the right steps, and you can often handle it yourself. The key is to find the leak early, clean the area properly, and use the correct repair method based on your roof type. Temporary fixes like tarps or tape can help in emergencies, but don’t wait too long to make a permanent repair.
Regular roof inspections and proper maintenance can prevent leaks from happening. If the leak is too big or you’re unsure what to do, we always recommend calling a professional.
You can reach out to RBG Roofing Ltd at 07304 082599 if you're in Forest of Dean or nearby areas.
FAQs
1- How long do flat roof repairs last?
Temporary repairs can last a few months, while proper patching or sealing can hold up for several years. The lifespan depends on the material and weather conditions.
2- How much does it cost to fix a leaking flat roof?
Small DIY repairs can cost as little as £20 to £50. But if you hire a professional, the cost can range from £300 to over £3000, depending on the damage.
3- Can roof leaks get worse over time?
Yes, if left untreated, leaks can grow and lead to serious problems like mould, rot, or structural damage. It’s best to fix them as soon as possible.
4- Should I replace or repair my flat roof?
If the leak is minor and the roof is in good shape, a repair is enough. However, if the roof is very old or has many problems, a full replacement might be more cost-effective in the long run.
