EPDM · TPO · PVC · Mod Bit · Dec-Tec
Flat Roofing In Philadelphia
Rowhomes, twins, commercial buildings, back additions — most of Philadelphia is flat up top. We know how these roofs fail, where they leak, and which membrane makes sense for your building.
20+ Years Flat Roofs
Thermal-Drone Detection
24-Hr Leak Response
Free Estimates
Get Your Free Flat Roof Inspection
Leaking, ponding, or just want to know how much life it has left?
Free, no-obligation, itemized. We’ll tell you straight what it needs.
Rowhomes · Twins · Commercial
A Different Animal From
A Pitched Roof
Flat roofs are everywhere in Philadelphia. Rowhomes, twins, commercial buildings, additions off the back of the house — most of them have a flat or low-slope roof up top. They hold up well when they’re done right, and you want a roofer who works on them all the time, not one who touches a flat roof twice a year.
We’ve been installing, repairing, and replacing flat roofs across Philadelphia and the surrounding areas for over 20 years. We know how these roofs fail, where they leak, and which membrane makes sense for your building. If it were our own roof, that’s the straight answer we’d want — so that’s what we give you.
Matched To Your Building
Flat Roof Systems
We Install
There’s no single “flat roof.” The right system depends on your building, your budget, and whether anyone’s going to walk on it.
01
EPDM Rubber
A proven single-ply rubber membrane that’s affordable, dependable, and lasts for decades. A workhorse on Philadelphia flat roofs.
02
TPO
A bright white single-ply membrane that reflects heat and keeps energy bills down. Popular on commercial buildings for good reason.
03
PVC Membrane
Chemically welded seams and strong resistance to grease and ponding water. A solid choice for restaurants and commercial roofs.
04
Modified Bitumen
A multi-layer asphalt-based system that’s tough underfoot and handles foot traffic well.
05
Dec-Tec Vinyl
A walkable, waterproof surface that works beautifully when the flat roof doubles as a deck or terrace. Few local roofers install it — we do.
06
PMMA
A liquid-applied resin that cures fast and seals the tricky drains and penetrations other systems struggle with.
Not sure which one fits? That’s what the free inspection is for. We’ll walk you through the trade-offs in plain English, no sales pressure.
Where They Actually Fail
Flat Roof Repair
A flat roof rarely leaks in the middle of the field. It leaks where things join, meet, or get penetrated. Nine times out of ten, the trouble is in one of these spots.
01
Seams
Where two sheets of membrane meet and the bond starts to open up.
02
Drain Boxes
Standing water and clogged drains put constant stress on the weakest part of the roof.
03
Pipe Flanges
The boots and collars around vents and pipes dry out, crack, and let water in.
04
Flashing
Where the roof meets a wall, a parapet, or a chimney.
We fix the actual failure, not just the wet spot on your ceiling. On a flat roof especially, the leak inside is often several feet from where water is really getting through the membrane — which is why we don’t guess.
If you’ve got an active leak, don’t wait on it. Garrison offers 24-hour emergency response for flat roof leaks, so a bad seam on a rainy Sunday gets handled, not scheduled for next week. If the trouble turns out to be a broader failure rather than one spot, our roof repair team can walk you through the options.
Thermal-Drone Imaging
Water Travels
We Find the Leak
Before We Touch It
Here’s where flat roofs get frustrating: water gets under the membrane and travels. It can move ten feet across the roof before it finds a seam in the deck and drips inside. Patch the spot below the drip and the leak comes right back, because you never touched the real entry point. So Garrison uses thermal-drone imaging to find it. The drone reads temperature differences across the whole roof surface and shows us exactly where moisture is trapped under the membrane, even when nothing looks wrong from the ground.
On flat and commercial roofs, that’s the difference between fixing a leak once and chasing it for months. Almost no local roofer offers it — and it’s a big reason property managers call us.
When Patching Stops Making Sense
Flat Roof Replacement
When a flat roof reaches the end of its life, patching stops making sense. If the membrane is brittle across the whole surface, if seams are opening up everywhere, or if water has been sitting in the insulation for years, a full flat roof replacement is the smarter spend.
We’ll tell you honestly which situation you’re in. After we inspect the roof, we show you photos and give it to you straight: repair will hold, or it won’t. If a repair will buy you several more good years, we’ll say so, even though it’s the smaller job. That honesty is the whole point of Garrison. For a full tear-off and rebuild, our roof installation and replacement crew handles the entire process.
Portfolio Roofing
Apartments · Mixed-Use · Commercial
Commercial & Multi-Property
Flat Roofs
A lot of Philadelphia’s flat roofs sit on apartment buildings, mixed-use properties, and commercial spaces. If you manage a portfolio, you need a roofer who shows up fast, documents everything, and keeps small problems from becoming capital expenses. Our documented inspection reporting — photos plus a written report — gives you the paper trail you need for budgeting and for coordinating repairs across buildings. If you oversee apartments, condos, or a commercial portfolio, our property management team is built for exactly this.
Why Owners Call Us
Why Property Owners Call
Garrison for Flat Roofs
20+ years of flat and low-slope experience across Philadelphia and surrounding areas
In-house crews, no subcontractors — the people who show up work for Garrison
Thermal-drone leak detection — we find hidden moisture instead of guessing
Every major membrane — EPDM, TPO, PVC, modified bitumen, PMMA, and Dec-Tec
GAF Certified Residential Roofing Contractor and a certified Spanish-speaking team
Documented inspections and free, no-obligation estimates
Straight About Pricing
What a Flat Roof Costs
Flat roof pricing depends on the system, the size, the condition of what’s underneath, and how much tear-off is involved. A single-seam repair and a full membrane replacement are nowhere near the same job, so we won’t throw a fake number at you online.
What we can promise: the estimate is free, itemized, and no-obligation. You’ll know what the work costs, and why, before we start.
Drag The Handle
Flat Roof Work,
Before and After
A storm-beaten low-slope roof rebuilt into a finished, waterproofed surface.
Recent Flat Roofs
Membranes We
Put Down
EPDM, TPO, modified bitumen and Dec-Tec on Philadelphia rowhomes and commercial buildings. Tap any photo to open it full size.
Straight Answers
Frequently Asked Questions
What’s the difference between TPO, EPDM, and modified bitumen?
EPDM is a black rubber single-ply membrane that’s affordable and long-lasting. TPO is a white single-ply membrane that reflects heat and helps with energy costs, which is why it’s common on commercial roofs. Modified bitumen is a multi-layer asphalt-based system that’s tough underfoot. They all work — the right one depends on your building, your budget, and whether the roof gets walked on.
How long does a flat roof last?
A well-installed flat roof generally lasts a couple of decades. The exact lifespan depends on the membrane, the quality of the install, and how well drainage and seams are maintained. Standing water and neglected drains are what cut it short, so regular inspections and keeping the drains clear go a long way.
Why do flat roofs leak at the drain box?
Because the drain box is the lowest, hardest-working point on the roof. Water collects there, debris clogs it, and that standing water puts constant pressure on the seams and flashing around the drain until the seal breaks down. It’s one of the most common flat roof leaks we fix, and keeping drains clear is the best way to prevent it.
Is Dec-Tec better than traditional rubber roofing?
It depends on what you need. Dec-Tec is a walkable vinyl membrane, so it’s the better pick when the flat roof also serves as a deck or terrace. Traditional EPDM rubber is a great, cost-effective choice for a roof nobody walks on. We install both, so we’ll recommend based on how you’ll use the space — not on what earns us more.
Free & No-Obligation
Get Your Free
Flat Roof Estimate
Leaking flat roof, or just want an honest read on how much life it’s got left? Get a free inspection from a roofer who works on flat roofs every week.