A mechanically attached sheet over an old roof fails at the fasteners first, and wind finds them. A property manager should check how the existing roof will hold a recover before ordering any single-ply system, because the old layers set the limits on weight, moisture and attachment. Versico is a single-ply roofing brand offering EPDM, TPO and PVC membranes with insulation and accessories. We install and repair these system types on Bronx buildings, and a recover over a dry existing roof is one of the jobs where the choice matters most.
Recovering an Existing Roof
A recover puts a new membrane over the old roof instead of tearing the old one off. It saves disposal cost, shortens the job and keeps the building drier during work. It only works if the old roof is sound: dry insulation, a deck that carries the weight and a surface that accepts the new layers. A roof with two layers already often cannot take a third under building rules.
We test before we commit. Moisture scan, core cuts and a deck check tell us whether the old roof is a base or a burden. Where it is a base, a cover board over the old surface and a new single-ply sheet make a fresh roof. Where it is a burden, we say so and price the tear-off. That decision, recover or overlay against full tear-off, is made from the test results and not from the budget.
Preparation on the old surface decides how well the recover bonds. Blisters are cut and patched, loose gravel is swept or removed, open seams are sealed and high spots are shaved. A cover board goes over the old membrane to give a flat, clean base for adhesive or fasteners. Skipping that layer lets every ridge and ripple in the old roof telegraph through the new one. The proposal lists the old roof's layer count and age beside the new system, so the owner sees what is being kept and what is being added.
EPDM, TPO and PVC
EPDM is a rubber sheet, flexible in the cold, joined with tape or adhesive. TPO is a thermoplastic with welded seams and a reflective face. PVC is a thermoplastic with strong chemical and grease resistance. Each is available as a roll and in prefabricated pieces for flashing.
The family follows the building. A simple apartment roof with heavy superintendent traffic does well with EPDM. A large warehouse with welded seams and a cool surface does well with TPO. A roof under restaurant exhaust does well with PVC. We name the family in the scope and explain why it was chosen.
Prefabricated accessories matter as much as the roll. Pipe boots, inside and outside corners, and curb wraps come ready-made for the system, which saves field welding on awkward shapes. Where a detail does not fit a prefab part, a field-fabricated flashing is cut from the same sheet and welded or taped to match.
Shoreline and Wind-Exposed Buildings
On October 29, 2012 Sandy's flood reached roughly 17 percent of the city; Throgs Neck stood 3.4 feet under water, City Island fell in the mandatory Zone A evacuation, and the Bronx counted about 49,000 outages. Roofs sit above flood water, but shoreline buildings take stronger wind, wind-driven rain and spray, and edge details are tested harder.
For buildings in Throgs Neck and City Island, we set attachment for the exposure, with closer fastener spacing at the perimeter and corners, and we use heavier edge metal. A mechanically attached sheet is checked at every fastener row. A fully adhered sheet is checked for adhesive coverage on a test patch before the main run.
Salt and humidity add a maintenance angle on shoreline roofs. Fasteners, plates and metal edge pieces corrode faster near the water, so we specify corrosion-resistant fasteners and check them on each visit. A rusted plate that loses its grip lets the sheet lift in the next blow.
Port Morris and Harlem River Yards
In Port Morris, the Harlem River Yards waterfront industrial property covers 96 acres, and its 28 acre intermodal rail facility connects through the Oak Point Link, which opened in 1998. The Bruckner Expressway (I-278) crosses Port Morris. Industrial roofs in a waterfront district see open exposure, which argues for secure attachment and tight edge details.
Industrial roofs also carry heavy rooftop equipment. A sheet that is welded to prefabricated flashings around each curb gives a durable detail, and a walk-pad route keeps the service traffic off the open sheet.
Rail and truck yards also throw debris onto roofs. Gravel, dust and litter fill drains and scour surfaces, so industrial roofs get a heavier maintenance schedule, with drains cleared after storms and after any nearby construction.
Repair and Maintenance of Single-Ply
Single-ply repairs start with finding the entry. We probe seams, check flashings and test curbs. Patches use compatible material, a cleaned surface and, for thermoplastic, a hot-air weld. Taped EPDM seams are repaired with new tape on a primed surface. A seam failure that keeps coming back along one line points to a moving substrate or an aging sheet.
Maintenance keeps repairs small. Twice a year we clear drains, probe seams, check fasteners where visible and note the condition of the surface. Records go in the roof file for the owner.
How We Install and Document
We install to the manufacturer's published requirements: substrate preparation, insulation, fastening or adhesive, seam welding or taping, flashing heights and terminations. Each day is photographed, and weather and materials are logged. Warranty availability is up to the manufacturer's program, and the owner sees the terms when the scope is set. Our warranty management work keeps the paper in order afterward.
Ida's record hour of 3.15 inches in 2021 is why drainage is checked on every recover, since a new sheet over a roof that ponds is still a pond.
Cost, Alternates and Code
Price follows roof area, attachment, cover board, insulation, penetrations, access and the amount of repair on the old roof. The Department of Buildings lists the 2022 NYC Construction Codes. They answer filing questions. We compare with other makers, such as Holcim Elevate and GAF, and price a recover against a tear-off so the owner sees both.
Commercial Roofing Questions
What stops a third layer from going on an old roof?
Building rules and the deck's capacity set the limit. We count the layers with a core cut and check the weight. Two layers are often the practical ceiling, and a roof at that limit needs tear-off.
Will a recover trap moisture in the old roof?
It can if the old insulation is wet. That is why we scan before we decide. A recover over dry material is sound. A recover over wet material hides the problem and spreads it.
Why is wind such a concern for a mechanically attached sheet?
Fasteners hold the sheet at the laps, and a gust can flutter the sheet between rows. Closer spacing at corners and edges, and a firm edge termination, keep it down.
Can I choose the family without a survey?
You can, but the survey often changes the choice. Drains, deck, exhaust and traffic all steer it. A cheap system on the wrong roof costs more in the end.
How do you handle tenants during a recover?
A recover is quieter and faster than a tear-off, with less debris. We still plan hoisting, noise windows and access with the superintendent, and we tell tenants the schedule.
Send the Roof Age and the Number of Layers You Believe It Has
Tell us the building type, the roof age and the last tenant complaint, and ask for a flat-roof walk before anyone writes a scope. We will test whether the old roof can take a recover.
Request a Roof Assessment