Flat roofs are unique in their simple, functional design and space-saving ability, but they come with trickier leaks than in a traditional roof. If you are facing such a leak, don’t panic! Our guide will help you spot the signs, understand the causes, and handle the repairs. This blog is intended for personal flat roofs, if a leak has been discovered in a roof you are building, it is often best to bring in an independent roof testing company to be transparent with your client about roof leaks and where roof repairs are required.
Table of Contents
- Indications of a leak
- Repairing leaks
- How to Handle a Leak During Heavy Rainfall
- Temporary Fix for a Leaking Flat Roof
- Concrete Flat Roof
- Fibreglass Roof
- Rubber Roof
- Felt Roof
- Finding the leak
- Common causes of flat roof leaks
- Damaged or Deteriorated Flashing
- Thermal Movement
- Ponding Water
- Seams and Overlaps
- Blistering
- Age
- Delamination
- Detailing Around Vents
- Poor Installation
- Structural Issues or Poor Design
- Prevention of leaks
- Does a Leaking Flat roof come under Home Insurance?
- Conclusion
- FAQs about roof testing
- About IntegriTest
Indications of a leak
If you suspect your flat roof might be leaking, keep an eye out for these warning signs:
- Damp patches on your ceiling
- Water pooling on the roof surface
- Cracked or peeling paint on the ceiling
- Visible mould or mildew
Repairing leaks
If you find yourself with a leak, there are a few actionable repair methods to temporarily keep the water out and reduce water damage while waiting for a professional.
1. How to Handle a Leak During Heavy Rainfall
If you notice a leak while it’s raining, use a bucket to catch the water and minimise damage. You can also apply a temporary waterproofing tape over the area to prevent further leaking until the rain stops.
2. Temporary Fix for a Leaking Flat Roof
For a quick fix before a full repair, clean the affected area and apply roofing sealant as directed in its instructions.
3. Concrete Flat Roof
Clean the surface and apply a bitumen primer. If necessary, a professional can patch over cracks with torch-on felt.
4. Fibreglass Roof
For fibreglass roofs, apply a small amount of acrylic sealant to the affected area. For a more permanent fix, sand the area, clean it with acetone, and laminate a patch with resin.
5. Rubber Roof
Use lap sealant for small leaks. For larger issues, a patch repair with self-adhesive rubber tape is the best bet.
6. Felt Roof
Felt roofs can be repaired using acrylic-based waterproofing paint for small gaps or by replacing the damaged felt for larger issues.
Finding the leak
Locating a leak can be challenging, particularly with flat roofs, but it’s possible to identify one without the need for specialised tools.
- Wait for a dry period of at least three days and choose an evening to begin.
- Look for any steam or warmth rising from the roof, which may indicate heat escaping through the leak.
- Look for signs like discolouration, dirt rings, or depressions that suggest water pooling.
- Spray water on the areas you identified in steps 2 and 3, one at a time. After each spray, wait for a couple of hours and check if any water reappears on the ceiling below.i
Common causes of flat roof leaks
Understanding the root causes of flat roof leaks is key to prevention and repair. There are many reasons but we cover the more common culprits here briefly, for more detail visit our article on the subject.
1. Damaged or Deteriorated Flashing
Flashing is made to cover seams and prevent leaking in vulnerable areas. However, if it is damaged or deteriorated, it could cause leaks and need to be repaired or replaced.
2. Thermal Movement
Temperature changes may cause different materials to expand and contract at different rates, causing cracks if the roof cannot resist it.
3. Ponding Water
Flat roofs should have a slight pitch to allow for water drainage, however, if a depression forms in the roof, it can cause pooling. If water pools, it can seep through the roofing material over time.
4. Seams and Overlaps
Where different roofing materials meet, leaks can easily occur, especially if seams haven’t been properly sealed.
5. Blistering
Blisters can form when moisture gets trapped beneath the roofing material. When they burst, leaks can result.
6. Age
The lifespan of flat roofs depends on the materials used. Traditional felt roofs might last only 15-20 years, while modern materials can last for decades.
7. Delamination
This happens when layers of roofing material separate. It can create cracks and other issues, leading to leaks.
8. Detailing Around Vents
Areas around vents and pipes are common leak points. Proper sealing is especially crucial here.
9. Poor Installation
If the roof wasn’t installed correctly, it might have weak spots that are prone to leaks. Always ensure you hire qualified, trusted professionals for installation.
10. Structural Issues or Poor Design
If the roof structure is flawed, it can lead to improper drainage and, therefore, leaks. Always ensure your roof design is sound.
Prevention of leaks
It’s always better to prevent a problem than to fix it later. Here’s how to maintain your flat roof:
- Conduct regular inspections to check for visible damage, water pooling, or heat loss.
- Clear any debris, such as leaves or dirt, to avoid water buildup.
- Trim any overhanging tree branches, as they can fall and damage the roof.
Does a Leaking Flat roof come under Home Insurance?
Unfortunately, most of the time, it won’t. However, you may be one of the exceptions, therefore, make sure to keep records of any damage and repairs, including photos.
Conclusion
Flat roof leaks can be a real nuisance, but with regular maintenance and a proactive approach, you can keep your roof in good shape. Don’t hesitate to reach out to professionals if you’re unsure about any repairs. Keeping your home dry and safe is worth the effort!
FAQs about Roof Testing
What is roof testing?
Roof testing involves checking a roof for leaks, testing its structural integrity and overall condition, and ensuring your roof can withstand the elements. Visit our homepage to see the roof tests that we provide.
How often should I test my roof?
It’s wise to inspect your roof at least twice a year and after heavy storms, especially if it covers your business or you are renting, since a leak could prevent business from being carried out. For more information, visit our warranty inspections page.
How long can my roof last?
If you do not know the date your roof was installed or worry damage might have lowered its lifespan you can call us in to assess how long until your roof needs replacing. If not we give information on how long roofs should last on another of our articles on Which Flat Roof Material is Best.
About IntegriTest
IntegriTest has a reputation for being professional, collaborative, precise and thorough in our inspections and testing. We are trusted by manufacturers, latent defect insurers, principal contractors, waterproofing contractors and estate management companies across the UK to perform our varied services.
Article written by Ben Flood
iMethod from: ( https://www.roofingmegastore.co.uk/blog/flat-roof-leaking.html, paragraph 18, accessed 6/12/24)
