Flat roofs have several distinct advantages, but the fact that they don’t have much of a slope also makes them more prone to leaks. Unfortunately, the cause of these leaks can be a little tricky to pinpoint.
Are you desperately wondering why your flat roof keeps leaking? We’ll explore the most common causes — and how to fix them.
1. Improper Installation
Unfortunately, improper installation is one of the most common causes of leaks in flat roofs. Improper installation can occur in the form of inadequate sealing or flashing and, in some cases, faulty membrane installation.
Having your roof assessed by an independent third-party — a contractor who didn’t install the roof — is advisable in these cases.
2. Damaged Roofing
Pooling water can cause roofing materials to develop blisters, while extreme weather or impact with an object can also damage the roofing materials like single-ply roofing (EPDM or TPO) or modified bitumen. Even small tears and cracks can quickly wreak havoc.
Get your flat roof repaired as soon as reasonably possible to minimize the damage and prolong its lifespan. Here are the most common fixes performed during roof repairs that you need to be aware of.
3. Problems with Flashing and Roof Penetrations
Flashing — the metal strips installed around the roof’s seams and edges — is absolutely critical to a properly-functioning roof. When it’s installed incorrectly or becomes damaged over time, leaks are almost inevitable. Water trickles into the home or building slowly in these cases.
Roof penetrations like skylights, vents, and chimneys also create vulnerable areas where leaks can develop. Flashing and sealants are used to prevent water damage in these spots, but damage or incorrect installation can cause leaking.
Poorly maintained gutters can also contribute to roof damage. Fortunately, these issues are usually minor when caught early and repaired promptly.
4. Water Pooling and Inadequate Drainage
Despite what their name suggests, flat roofs aren’t completely flat. Instead, they have low slopes that allow water to drain. A flat roof can start leaking when the slope isn’t sufficient, or the drainage path is obstructed. That’s because water begins to pool in certain spots, weakening and damaging the roof over time and causing water to leak into the home or building.
Being proactive is essential if water is pooling on your flat roof, as the problem will only get worse with time.
5. Extreme Weather Events
Heavy rain, hailstorms, snowstorms, and even strong winds can all cause a flat roof to sustain damage. Homeowners who notice that their flat roof suddenly started leaking after an extreme weather event can bet that there’s a correlation.
In some cases, heavy rain overwhelms the roof’s drainage system, while storms can cause objects like tree branches to obstruct it. Extreme weather can even cause structural damage in some cases.
You know what to do — don’t wait; call a competent roofing contractor as soon as possible to assess and repair the damage.
6. Your Roof Is Past Its Expiration Date
Most flat roofs have an expected lifespan of around 15 years. Homeowners and businesses can help to ensure that the roof lasts as long as possible by facilitating regular maintenance.
If your flat roof is already nearing the end of its lifespan, it’s also important to consider that roofing materials degrade over time. No matter how well you maintain your flat roof, it will need to be replaced once it reaches the end of its functional life.
7. Poor Maintenance
Ideally, a flat roof should be inspected at least once a year. This enables roofing professionals to identify small problems before they have the chance into major repair jobs. Be sure you know what type of flat roof you have, as different materials handle weather differently and require specific maintenance.
Built-up flat roofs can last 15 to 20 years, while you can reasonably expect to replace a modified bitumen roof after 10 to 20 years.
Pitched roofs generally offer better leak protection than flat roofs because their steep slope allows rain, snow, and debris to run off more easily, minimizing water pooling. In contrast, flat roofs have a low slope, making them more prone to standing water and drainage issues that can lead to leaks. Learn more about how roof slope and pitch affect leak protection and overall performance.
Proper installation and regular maintenance are crucial for both types, but pitched roofs naturally have an advantage when it comes to shedding water. This is one reason many homeowners prefer pitched roofs in areas with heavy rainfall. Learn more about remodeling a flat roof to pitched.
