Flat Roof Repair in NJ for Commercial and Multi-Family Buildings
R&E Roofing repairs flat and low-slope roofs on commercial buildings and two- and three-family houses across Essex County. We trace the leak to the drain, flashing, seam or penetration that failed, photograph it, and give you a written estimate before the repair. EPDM, TPO, PVC, modified bitumen and built-up roofs.
Leaking now? Emergency calls taken nights and weekends. R&E usually calls back within about 2 hours. Office hours are Monday to Friday, 9 a.m. to 5 p.m.
R&E Roofing, 573 Valley Street, Orange, NJ 07050 · Updated
Request flat roof repair
Tell us the building address, where water shows up inside, whether it is leaking now, and the roof material if you know it. Pick Flat Roof Repair in the service list.
Or call (667) 204-1609Emergency calls taken nights and weekends. R&E usually calls back within about 2 hours. Office hours are Monday to Friday, 9 a.m. to 5 p.m. Forms sent after hours are answered during office hours.
Your flat roof, in a few lines
Choose Flat Roof Repair, or Emergency Roof Repair if water is coming in now.
Flat roofs R&E repairs in Essex County
R&E takes flat roof repair requests from two kinds of buildings in Essex County:
- Commercial buildings. Storefronts, mixed-use buildings with apartments over shops, offices and small warehouses, where rooftop units, exhaust fans and drains share the roof with the membrane. For commercial leaks that are not on a flat roof, see commercial roof repair.
- Two- and three-family houses. The flat rear roofs on houses in Newark, East Orange, Irvington and Orange, often behind a brick or framed parapet with a scupper or a single drain.
If you need a new flat roof rather than a repair, that is covered on new and replacement flat roofs. This page is about finding and fixing the leak on the roof you have.
How a flat roof leak is found
A flat roof leak is hard to find because the water rarely drips straight down. Here is the order that works:
- Mark every spot where water shows up inside. Note the ceiling or wall, the date, the weather, and whether it drips during rain or hours after. Water that appears only after snow melts points somewhere different from water that appears in wind-driven rain.
- Start the roof search uphill and upstream of the stain. On a flat roof, water that gets past the membrane can run along the deck, soak sideways through insulation and drip far from where it entered. The stain shows where the water ended up, not where it got in.
- Check the openings before the open field. Drains, scuppers, parapet flashing, coping joints, skylight and hatch curbs, pipe and vent flashing, and rooftop equipment curbs are interruptions in the membrane. They are checked first, then seams and laps between them.
- Find out whether the insulation is wet. A patch on top of wet insulation traps the water in the roof. When insulation under a split or seam is soaked, that section is cut out and replaced before the membrane is closed again.
- Photograph the failure and put the scope in writing. R&E gives a written estimate with photos, so the owner, property manager or tenant can see the opening that failed and what the repair covers.
Carlisle’s EPDM restoration instructions call for the same order at drains and delaminated areas: identify wet insulation, remove it, install new insulation, then new membrane (Carlisle SynTec). For a longer walk-through, read R&E’s flat roof leak repair guide.
Where flat roofs leak: drains, parapets, skylights, hatches and seams
These are the spots where a flat roof membrane is cut, turned or joined. Each one fails in its own way.
Drains, scuppers and ponding water
Ponding water is “water which remains on a roof 48 hours or longer”, and ARMA recommends at least ¼ inch of slope per foot so a roof drains freely. On existing roofs, ponding usually starts at a clogged drain strainer, a scupper blocked by debris, a sagging deck, or crushed insulation. The repair clears or rebuilds the drain or scupper, replaces wet insulation around it, and corrects the low spot where that can be done without a full tear-off. (ARMA)
Parapet walls and coping
On row-style commercial buildings and two- and three-family houses, the flat roof often meets a brick parapet. Leaks come from open coping joints, cracked mortar, and base flashing that has pulled away from the wall. Water entering the top of a parapet can show up inside a floor below, so the wall is checked along with the roof.
Skylights and roof hatches
Skylights and roof hatches sit on curbs, and the membrane has to turn up the curb and be sealed under the frame. Leaks at these spots usually come from the curb flashing, the corners, or a cracked frame gasket, rather than the glass. A hatch that is opened often also wears the membrane around it.
Pipes, vents and rooftop equipment
Every plumbing vent, exhaust, gas line and equipment curb is a hole in the membrane. Flashing boots shrink and crack, sealant pockets dry out, and equipment vibration loosens the seal. HVAC service traffic can also puncture the membrane near units.
Field seams and laps
Membranes come in rolls, so a flat roof has seams. Glued or taped EPDM seams can let go, welded TPO or PVC seams can fail where the original weld was weak, and the laps of modified bitumen or built-up roofs crack and open as the surface ages.
How each flat roof membrane is repaired
The repair has to match the roof. A patch that bonds to one membrane will not bond to another, so it helps to tell R&E what the roof is if you know. If you do not, say so; it is identified on the roof.
EPDM (rubber)
A single-ply synthetic rubber sheet, usually black, glued, fastened or held down with stone ballast. Common failures are seam separation, shrinkage that pulls flashings away from walls and curbs, and punctures.
- Clean and prime the aged membrane, then patch with EPDM membrane or self-adhered EPDM and seal the edges
- Re-seal or overlay opened seams with seam tape or a cover strip
- Re-flash shrunken edges at walls, curbs and drains
TPO and PVC (white or light single-ply)
Thermoplastic sheets whose seams are welded with hot air. A weld that was too cold or contaminated at install can open years later, and the sheet can be punctured by foot traffic or dropped tools.
- Clean the area and hot-air weld a patch of compatible membrane
- Re-weld or strip-in failed seams
- Replace or re-weld flashings at curbs and penetrations
Modified bitumen
Asphalt-based rolled roofing in one or more plies, torch-applied, mopped or self-adhered, often with a granule surface. It ages with surface cracking, blisters and open laps.
- Cut out blisters, dry the area and patch with new ply
- Seal open laps with torch-applied or self-adhered patches
- Restore exposed areas where granules have worn away
Built-up roofing (BUR, tar and gravel)
Several layers of felt and asphalt with a gravel surface, found on older commercial and multi-family buildings. Leaks start where the gravel has scoured off, at blisters, and at flashings.
- Move gravel aside, repair the plies with compatible asphalt and felt, then replace the gravel
- Repair blisters and cracks with hot or cold-applied asphalt
- Rebuild base flashing at walls and curbs
Can EPDM roofing be patched?
Yes, when the membrane around the damage is still sound. Here is what a proper EPDM patch involves, from the manufacturers’ own repair instructions:
- Clean it twice. Aged EPDM is scrubbed with soapy water, rinsed and dried, then cleaned again with a splice wash (Elevate).
- Prime where the product calls for it. Self-adhered EPDM patches go over a primed area that extends past the patch (Elevate).
- Overlap and round the corners. The patch must extend at least 3 inches past the damage in all directions, with rounded corners, so even a pinhole takes a patch at least 6 by 6 inches (Elevate).
- Know when a patch is not enough. On an Elevate EPDM roof with more than six punctures in any 100 square feet, the maker’s guide calls for overlaying the whole area with new membrane. Wet insulation under the damage is cut out and replaced before new membrane goes on (Carlisle SynTec).
The manufacturers’ instructions call for EPDM membrane, splice products and seam tape, not caulk or roof cement smeared over a split. That kind of quick fix also has to be scraped off before a proper patch can go on. For EPDM-only work, see rubber roof repair.
Repair, re-cover or replace, and what the “25% rule” means in New Jersey
There are three ways to deal with a leaking flat roof. A repair fixes the failed spot. A re-cover puts a new membrane over the old roof. A replacement tears the old roof off down to the deck and starts again.
The “25% rule” is Florida’s
Owners often hear that if more than 25 percent of a roof is damaged, the whole roof must be replaced. That rule is written into Florida’s building code: not more than 25 percent of a roof or roof section may be repaired, replaced or recovered in any 12-month period unless the whole roof or section meets the current code. In 2022 Florida added an exception for roofs built, repaired or replaced under its 2007 code or later; for those, only the part being worked on has to meet the current code (Florida Senate).
What New Jersey’s code says
Work on existing buildings in New Jersey falls under the rehabilitation subcode of the Uniform Construction Code. Its repair section says: “There is no limit to the amount of repair work which may be undertaken” (N.J.A.C. 5:23-6.4(a), NJ Department of Community Affairs). It does limit re-covering. The existing roof covering must be removed before a new covering goes on when:
- the existing roof is water soaked or has deteriorated so that it is not adequate as a base for more roofing;
- the existing covering is wood shake, slate, clay, cement or asbestos-cement tile; or
- the roof already has two or more applications of any type of roof covering (N.J.A.C. 5:23-6.4(e)7, NJ DCA).
The subcode itself says it does not decide whether a permit is needed; that is set in N.J.A.C. 5:23-2 (NJ DCA). Ask your town’s construction office about your building.
How the choice usually goes
- Repair when the failure is local and the membrane and insulation around it are sound.
- Re-cover only when the old roof is dry, sound enough to be a base, and not already two layers deep.
- Replace when insulation is wet across large areas, leaks keep appearing in new places, or the deck needs work. See new and replacement flat roofs and flat roof replacement cost in NJ.
If someone offers a roof coating
Liquid coatings, such as silicone or acrylic, are sold as a way to extend an aging flat roof. If you are offered one, ask: will wet insulation be found and cut out first, is the coating made for your membrane type, and what written terms come with it? A coating over a wet roof seals the water in.
What Essex County weather does to a flat roof
Public weather records for Newark, the nearest long-running station to Orange, show why flat roofs here wear at their seams and flashings (NOAA 1991-2020 normals):
- Rain. Newark averages 46.6 inches of precipitation a year, with about 12 days a year bringing an inch or more. A slow or blocked drain shows up on those days.
- Freeze and thaw. Newark averages 79.9 nights a year at or below 32°F but only 14.5 days that stay below freezing all day. So on about 65 days a year, water in an open seam or under lifted flashing freezes and thaws again.
- Snow. Newark averages 31.5 inches of snow a year. Snow piled against a parapet or around a drain melts slowly and keeps water on the roof longer.
What changes the cost of a flat roof repair
R&E prices each flat roof repair after seeing the roof and puts it in a written estimate with photos. These are the things that move the number:
- Which part failed: a single puncture or one vent boot is a small, local repair; a drain, a parapet wall or a long seam is more work.
- Membrane type: EPDM, TPO, PVC, modified bitumen and built-up roofs each need their own materials and methods.
- Wet insulation or deck damage found once the area is opened.
- Access: roof hatch, ladder or interior stair, building height, and occupied spaces below.
- Whether temporary protection is needed first while the weather clears.
For published cost ranges by type of damage, read the flat roof repair cost guide. For causes, fixes and costs in one place, see flat roof problems in NJ.
How a flat roof repair works with R&E
Call or send the request form
Give R&E Roofing the address, building type, where water shows up inside, whether it is leaking now, roof access, and the roof material if you know it.
The leak is traced on the roof
Drains, scuppers, parapet flashing, skylight and hatch curbs, penetrations and seams are checked, working back from where the water shows up inside.
Review the written estimate with photos
The estimate shows the failed spot and separates the repair from any wider work, such as wet insulation replacement or a section re-roof.
Approve the scope and the repair is made
The repair method matches the membrane, the failure point, drainage, weather and safe access.
Keep the records with the building file
Keep the photos, written scope, invoice and any follow-up recommendations together, so the next person on the roof knows what was done and where.
Flat roof leaking right now?
Emergency calls taken nights and weekends. R&E usually calls back within about 2 hours. Office hours are Monday to Friday, 9 a.m. to 5 p.m. Until someone reaches the roof, catch the water inside, keep it away from lights and outlets, and take photos before you clean up. Do not walk a wet or icy roof.
For more on urgent leaks, see emergency commercial roof repair and emergency roof repair in NJ.
Flat roof repair questions
How much does flat roof repair cost in NJ?
It depends on which part failed, the membrane type, whether insulation or decking underneath is wet, and how the roof is reached. A single puncture is a small repair; a failed drain, parapet or long seam is larger. R&E prices each job after seeing the roof and gives a written estimate with photos. R&E's flat roof repair cost guide lists published cost ranges by type of damage.
Can EPDM roofing be patched?
Yes. The membrane is scrubbed clean, cleaned again with a splice wash, primed where the patch product calls for it, and covered with EPDM membrane or self-adhered EPDM. Elevate's repair guide for its RubberGard EPDM says the repair must extend at least 3 inches beyond the damage in all directions, with rounded corners, so a pinhole takes at least a 6 by 6 inch patch. The same guide says that when an EPDM roof it covers has more than six punctures in any 100 square feet, the whole area is overlaid with new membrane. A patch does not fix wet insulation underneath; that section is cut out and replaced first.
What is the 25% rule for roofing?
It is a Florida building code rule: not more than 25 percent of a roof or roof section can be repaired, replaced or recovered in any 12-month period unless the whole roof or section is brought up to the current code. Florida added an exception in 2022 for roofs built, repaired or replaced under its 2007 code or later. New Jersey's rehabilitation subcode is different. Its repair section says, "There is no limit to the amount of repair work which may be undertaken." What it does require is that the existing roof covering be removed before a new covering goes on when the old roof is water soaked or too deteriorated to be a base, or already has two or more layers. Whether your job needs a permit is a separate question for your town's construction office.
What causes flat roofs to leak?
Flat roof leaks usually start where the membrane is interrupted: drains and scuppers, parapet flashing and coping, skylight and hatch curbs, pipe and vent flashing, equipment curbs, and seams. Ponding water, freeze-thaw cycles and foot traffic speed up the wear. Because water can travel under the membrane and through insulation, the leak inside is often some distance from the opening on the roof.
Should I repair or replace my flat roof?
Repair fits when the failure is local and the membrane and insulation around it are sound. Replacement comes up when leaks keep appearing in new places, large areas of insulation are wet, the membrane is worn across the roof, or the deck needs work. A re-cover over the old roof is limited in New Jersey: the old covering has to come off when it is water soaked, too deteriorated to be a base, or already two or more layers deep.
Can a flat roof be repaired in winter?
Often, but the method depends on the weather. Adhesives, primers and sealants have temperature limits set by their makers, and a wet or icy roof is not safe to work on. In cold or wet weather the first job may be to control the leak and protect the opening, with the permanent repair once conditions allow. Tell R&E the membrane type if you know it and whether water is coming in now.
Do you take emergency calls for flat roof leaks?
Yes. Emergency calls are taken nights and weekends, and R&E usually calls back within about 2 hours. Office hours are Monday to Friday, 9 a.m. to 5 p.m.
Do you repair flat roofs on two- and three-family houses?
Yes. R&E handles flat roofs on commercial buildings and on Essex County two- and three-family houses, such as the flat rear roofs on houses in Newark, East Orange, Irvington and Orange.
Essex County towns served from Orange
R&E’s office is at 573 Valley Street, Orange, NJ 07050, and its service area is Essex County. Call with the property address to confirm timing for your building.
Sources
Code, weather and manufacturer facts read October 24, 2026. Photos are CC0 or public domain and shown to illustrate, not as R&E jobs.
- New Jersey Department of Community Affairs, N.J.A.C. 5:23-6, Rehabilitation Subcode (sections 6.1 and 6.4), current through the N.J. Register of August 17, 2026, read October 24, 2026
- The Florida Senate, 2022 Special Session D bill summary, roof repair, replacement and recovering (the “25 percent” rule), read October 24, 2026
- Asphalt Roofing Manufacturers Association (ARMA), Ponding Water Basics, read October 24, 2026
- Elevate (Amrize Building Envelope), Roof Repair and Renovation guide: RubberGard EPDM membrane repair, read October 24, 2026
- Carlisle SynTec, Sure-Seal/Sure-White EPDM Roof Restoration installation instructions, read October 24, 2026
- NOAA NCEI, 1991-2020 annual climate normals, Newark Liberty International Airport (USW00014734), read October 24, 2026
Get the leak traced to the part that failed
Call R&E Roofing in Orange or send the request form. Emergency calls taken nights and weekends. R&E usually calls back within about 2 hours. Office hours are Monday to Friday, 9 a.m. to 5 p.m.