Roof Repair & Leak Prevention on Flat & Slope Roofs | Alliance Group

Once the roof leaks water into your home, there is already a trail of damage within your roofing system. Sadly, many roof leaks have the chance to sit and rot away at the different layers of roofing materials before they are even detected. Unlike straightforward, simple roofs, mixed slope roofs have more areas to protect that are prone to leaks. Flat roofs come with their own set of challenges, like ponding water. Below are actionable tips for leak prevention, but if you have an existing leak save yourself a headache and call a roofing professional for roof repair.


Inspect For Roof Damage

The best advice for preventing roof leaks is to perform regular roof maintenance while inspecting for damage. Look for anything out of place or with visible damage. After a storm hits is a great time to inspect your roof while clearing it of debris. One of our clients found they had missing pieces of ridge cap after hurricane Matthew. Look out for missing shingles, gutters, vents or other roof components.

Roof inspection for metal and modified bitumen flat roof. Residential roof repair for roof coating and to replace ridge caps.

One of our client’s existing roof problem areas.


On flat roofs, flying debris can hit and gauge the roofing membrane, making it susceptible to water damage. If you intend to patch an area of your flat roof, be aware of water that would have already soaked through to the layers below. Depending on the severity and time left alone, this type of damage may require a roof replacement.

Shingles, concrete, or clay roof tiles can suffer from cracks due to debris impact, old age or in some cases, even a shifting foundation.


Roof leaks caused by cracked or missing shingles and tiles.

Chipped and cracked roof tiles (top), missing and torn shingles (bottom).


Proper Air Ventilation

Badly installed (or a lack of) roof ventilation can cause rot and leaks. Water damage caused by condensation can easily go unnoticed for a long time because it occurs in a confined space.  Condensation in hot (insulated) or cold (open air) flat roofs are just as probable if not installed well. For a hot roof to not cause any condensation, the insulation layer must not have any voids at all.  A cold roof should have sufficient airflow, so be sure it isn’t being blocked by items stored in the attic. Insulation over the roof deck with airflow between the joists is ideal for avoiding cold roof condensation.


Secure Flashing, Joints & Edges

Places where materials end, join together or elevations change can become the ideal setting for leaks.

Check roof valleys, flashing, drip edges and eaves for damage. For example, a missing or broken drip edge would lead water into the fascia board and soffit, causing damage to the eaves. A damaged fascia board could allow moisture and nesting animals into your roofing system.

Replace flashing if worn or damaged. On flat or low sloped roofs, Gaco Seam Seal is an option for waterproofing these types of problem areas.


Waterproofing flashing and flat roof with silicone roof coating and seam seal. Roof coating for coastal marine environment.


Gaco Flash foam coating application for waterproofing and leak prevention in Florida.

We used Gaco Seam Seal and Flash Foam to seal this leak-prone commercial roof. See the project here.


Pooling water on a Flat Roof

An uneven surface and/or bad drainage are common causes of pooling water on flat roofs. One option is firring out the uneven areas with materials such as bitumen sheets. Spray polyurethane foam is another option for re-leveling a flat roof. SPF works best when used together with a UV resistant coating like Gaco’s S20 silicone roof coating. With this method, we can repair the cause of flat roof leaks while preventing future ones from forming. Good drainage can give you more time between needed roof maintenance. Therefore, make sure debris isn’t clogging your roof drain or gutter system.

Pooling water on flat roof. Flat roof in South Florida needs water damage repair.

A residential flat roof with pooling water.


Waterproof Roof Coating for Flat Roof Leak Prevention

Unless your flat roof is damaged beyond repair, one economical yet long-lasting option for leak prevention is silicone roof coating. We use Gaco Western products for our customers because they have a quality product backed by a labor and material warranty. Silicone roof coating has the strength and durability to be used on commercial roofs. This UV resistant coating stands up to pooling water.


Silicone roof coating on residential flat roof for coastal home.

Gaco silicone roof coating used to waterproof a residential flat roof.


Call us today to receive a free quote for roof repair, replacement, coating or maintenance.

(800) 822-ROOF (7663)