Flat roofing in New Jersey
The roof over the porch, the garage or the back addition is flat and holds puddles after it rains. Shingles need slope to shed water, so a roof that flat takes a different system. We work on flat and low slope roofs on houses in 14 New Jersey counties.
NJ HIC 13VH13268400 · Licensed and insured · Free inspection · Open 24 hoursModern Home Roofing & Chimney works on flat and low slope roofs over porches, garages and additions in 14 New Jersey counties under NJ HIC license 13VH13268400. Shingles need slope to shed water, so these roofs take a different system, and we price them that way. Every flat roof job starts with a free inspection, photos and a written estimate.
Why a flat roof cannot be treated like a shingle roof
A shingle roof works because water runs downhill over overlapping pieces. A flat roof has almost no slope, so water can sit on it for hours after a rain. Every seam and every edge spends that time under water, and shingles laid on a roof that flat leak at the laps.
Water on a flat roof finds the one weak seam. You usually see it first as a stain on the ceiling under the porch, the garage or the addition.
Signs your flat roof needs work
- Puddles that are still there a day or two after the rain stops.
- Blisters or bubbles in the roof surface.
- Seams or edges that are lifting or split open.
- Cracks around a skylight, vent or chimney that comes through the flat section.
- A stain on the ceiling under the porch roof, the garage or the addition.
- Shingles on a section that is too flat for them, with leaks where they overlap.
If the leak is on the sloped shingle part of the roof and not the flat section, that is a roof repair. We tell you which one it is after we have been up there. How roof repair works
How a flat roofing job works
A flat roofing job with us runs in six steps. The deck gets checked before anything new goes down, and your written estimate lists how long the work will take.
We inspect the roof, free
We get on the flat section when it is safe to, check the ceiling or the space under it, and photograph where water sits and where the seams are open.
You get a written estimate
Scope, materials and the price, on paper. If we open something up and find a problem underneath that changes the scope, we stop and show you before we touch it.
We take off the old roof
The old roofing comes off down to the wood deck, so nothing wet or failed gets sealed in under the new roof.
We check the deck
If boards are soft or rotted, you get photos and a price before we replace them. A flat roof needs a solid, even deck, or water collects in the low spots.
We put down the new roof
A membrane made for low slope roofs goes down over the deck. The seams get sealed, and the membrane is turned up and flashed at every wall, skylight and vent.
We clean up and walk you through it
We run a magnet over the lawn and driveway for nails before we leave. Then we go over the finished roof with you, with photos.
What a flat roof is made of
A flat roof is not quite flat. It pitches slightly toward an edge or a drain, and every part below has to keep water out while it waits to run off.
Deck
The wood under everything. It has to be solid and even, because every low spot becomes a puddle.
Membrane
The waterproof sheet across the whole roof. Common types are EPDM rubber, TPO and modified bitumen, and each one is laid and sealed differently.
Seams
Where two sheets of membrane overlap. Many flat roofs fail at a seam first, because it sits under standing water.
Wall flashing
Where the flat roof meets a wall of the house, the membrane has to turn up the wall and tuck in behind the siding.
Skylights and vents
Anything that comes through the roof needs its own flashing. Cracks around these are a common source of leaks.
Edge and drainage
Metal along the roof edge holds the membrane down and sends water into the gutter or out a drain, instead of back under the roof.
Puddles or a leak on your flat roof?
Get a free inspection
What to know about flat roofs
Why flat roofs are priced differently
They need a different system than a shingle roof, and we price them that way. When a house has both a sloped roof and a flat section, we look at both at the inspection and tell you what each one needs.
What winter does to a flat roof
Snow sits on a flat roof instead of sliding off. When it melts, the water has nowhere fast to go, and farther north and west, in Sussex, Warren and Morris, it can melt and refreeze on the seams for weeks. Near the shore, in Ocean and Monmouth, wind pulls at any loose edge.
Related work
Skylight leaking in the middle of the flat roof? See Skylight Installation and Repair. Water spilling off the edge: Gutter Installation. Building an addition with a flat section? See Roof Installation.
Check us out before we open up your flat roof
It depends on the size of the flat section, how the water drains off it, how much of the deck under it is soft, and what the roof has to meet, like a wall, a skylight or a vent. We do not quote over the phone. You get a written price after we have been on the roof.
Not on a roof that flat. Shingles rely on slope to run water off the overlapping pieces. On a flat or low slope section, water sits and backs up under them. These roofs need a different system than a shingle roof, and we price them that way.
A little, for a short time after a storm, is common. Water that is still there a day or two later means the roof has low spots or the drainage is blocked, and every seam under that puddle is working harder than it should. We photograph where it sits when we inspect.
It depends on the roof. Common flat roof membranes are EPDM rubber, TPO and modified bitumen, and each one is laid and sealed differently. We tell you which one we would put on your roof and why, and it is written into the estimate before work starts.
It depends on how much of it has failed. A single open seam or a loose edge can often be fixed. Blisters and leaks across the whole surface, or a soft deck, usually mean it is time for a new roof. You see the photos, so you do not have to take our word for it.
That is where many flat roofs leak. The roofing has to turn up the wall and tuck in behind the siding. When that detail fails, water runs down inside the wall and shows up on a ceiling or around a door below. We check the wall line when we inspect.
We work on flat and low slope roofs in Bergen, Essex, Hudson, Hunterdon, Mercer, Middlesex, Monmouth, Morris, Ocean, Passaic, Somerset, Sussex, Union and Warren counties. If your town is in one of those, we can come out.
Find out what your flat roof needs
Tell us what you are seeing. We come out, inspect it for free, and give you photos and a written price. If a repair will do the job, you will hear that from us. If you hire someone else, you owe us nothing.
Open 24 hours · NJ HIC 13VH13268400 · Licensed and insured