Low-slope and flat roofs
Flat roof repair in Long Beach, CA
Your flat roof has blisters, cracked seams or water standing on it for days after rain, and now it is leaking into the room below.
Flat roof repair fixes leaks and wear on low-slope roofs: blisters, split seams, failed drains, parapet leaks and worn coatings. Common on mid-century homes, additions, garages and apartments in Long Beach. Expect $395 to $1,620 for a typical repair, priced after our roofer inspects.
Flat roofs are not truly flat. They are built with a slight slope so water drains to an edge, a scupper or a drain. When that slope sags, or a drain clogs, water sits on the roof for days after a storm. Standing water finds every seam, crack and blister, and that is where flat roofs leak.
We repair all the common flat roof systems in Long Beach: hot mop built-up roofs, torch-down modified bitumen, TPO single-ply membranes and coated roofs. Each needs a different repair method and the right compatible materials. A patch made with the wrong product will not bond and will peel off in a season.
Hot mop, torch-down, TPO and coated roofs
Hot mop roofs are built from layers of felt set in hot asphalt, often with a gravel or cap sheet surface. Torch-down roofs use rolls of modified bitumen heat-welded in place. TPO is a white single-ply membrane with heat-welded seams. Many older flat roofs have been coated with elastomeric or acrylic coatings over the years.
We identify the system before we repair it, because a TPO patch will not stick to asphalt and asphalt products damage some membranes. Getting the materials right is what makes a flat roof repair last.
- Hot mop built-up roofs
- Torch-down modified bitumen
- TPO single-ply membrane
- Elastomeric and acrylic coated roofs
Where flat roofs fail first
Blisters appear when moisture or air trapped between layers expands in the heat, and they crack open over time. Seams and laps let go as adhesives and welds age. Flashing at parapet walls, where the roof turns up the wall, pulls away and lets water behind it. Drains and scuppers clog with leaves and debris and back water up.
Ponding is the big one. Water that sits for more than a couple of days after rain speeds up wear and finds any opening. Fixing a leak in a ponding area without addressing the low spot usually means another leak there next year.
- Blisters and alligator cracking
- Open seams and laps
- Parapet and wall flashing
- Clogged drains and scuppers
- Low spots that pond water
How we repair a flat roof leak
We cut out damaged material back to sound roofing, dry the area, check the decking underneath and replace any that is soft. Then we patch with compatible material, extending well past the damaged area, and seal the edges. On torch-down and TPO, seams are heat-welded. On hot mop, we rebuild the layers.
If water ponds, we can build up the low area with tapered material or add a scupper so it drains. Clearing and re-flashing drains and resealing parapet flashing are part of most flat roof repairs we do.
When to call about flat roof repair
Water standing for days
Puddles that remain more than 48 hours after rain point to a low spot or a blocked drain.
Blisters and bubbles
Raised bubbles in the roof surface that can crack and let water in.
Cracks and alligatoring
Surface cracking in a crisscross pattern, a sign the roof is drying out under the sun.
Seams pulling apart
Edges of the membrane or cap sheet lifting along the laps.
Leaks below parapets
Stains along the tops of walls under a parapet, where wall flashing has pulled loose.
Worn or peeling coating
A coating that has chalked, cracked or peeled, leaving the roof beneath exposed.
Typical cost in Long Beach
What flat roof repair usually costs
$395 to $1,620 for a typical repair
- Type of flat roof system
- Size and number of damaged areas
- Wet decking that needs replacing
- Drain, scupper or parapet work
- Correcting a ponding low spot
These are typical Long Beach ranges, and your real price comes after we inspect your roof. See every price range.
Flat roofs from Rancho Estates to downtown
Long Beach has more flat roofs than many people expect. The Cliff May homes in Rancho Estates were built with low-slope and flat roofs and wide eaves. Mid-century ranch homes across Los Altos and the Plaza often have flat sections over additions, family rooms and garages. Downtown, Alamitos Beach and along Ocean Blvd, apartment buildings and condos are mostly flat, and so are many older commercial buildings near the port and along Long Beach Blvd.
Our sun is hard on flat roofs. Strong UV dries out asphalt and coatings, and long dry summers mean cracks open up unnoticed. Then a winter atmospheric-river storm puts several inches of rain on the roof in a few days, and every clogged drain and low spot shows itself. Near the coast, salt air corrodes metal edges and drain parts faster.
How the job runs
How our crew handles flat roof repair
- 1
Identify the system
Our roofer confirms whether it is hot mop, torch-down, TPO or coated before planning repairs.
- 2
Find leaks and low spots
We check seams, drains, parapets and ponding areas, and the ceiling or attic below.
- 3
Cut out the damage
We remove failed material back to sound roof and replace any wet decking.
- 4
Patch and weld
We install compatible patch material, heat-welding or rebuilding layers to match the system.
- 5
Fix drainage
We clear and re-flash drains, reseal parapets and correct low spots where needed.
FAQ
Flat Roof Repair questions
How do I know what type of flat roof I have in Long Beach?
A gravel or granular black surface is usually hot mop or torch-down, a smooth white membrane is often TPO, and a painted-looking white or gray surface is a coating. Our roofer will confirm it on the first visit. It matters because repairs must use compatible materials.
What does flat roof repair cost in Long Beach?
Our typical range is $395 to $1,620 for a flat roof repair. Patching a single blister or seam is at the low end, while repairs that include decking, drains or ponding correction cost more. We confirm after the inspection.
Is water standing on my flat roof after rain a problem?
Small puddles that dry within a day or two are normal. Water that sits longer speeds up wear and is where most flat roof leaks start. We can clear drains, add a scupper or build up the low spot.
Can you repair a flat roof on a Long Beach apartment building?
Yes. We repair flat roofs on apartments, condos and small commercial buildings, and we schedule around tenants and access. For larger buildings, we document the roof's condition so owners and HOA boards can plan.
Should I coat my flat roof or repair it first?
Repair comes first. A coating over open seams, wet insulation or blisters will trap the problem rather than fix it. Once the roof is sound, a coating can add years and reflect heat.
Where we do this work
Flat Roof Repair around Long Beach
Our crews do this work across Long Beach and the cities around it. A few of the places we cover:
A leak, a quote, or a question about your roof?
Call Denco at (562) 414-1770. Someone answers 24 hours a day, and our crews work out of Long Beach and La Mirada.