TPO. EPDM. Modified Bitumen. Correctly Diagnosed.
Flat roofs fail differently than pitched roofs -- and they require repairs that account for how the specific membrane system in place actually moves, bonds, and ages. A TPO repair performed with the wrong technique or an incompatible sealant does not solve the problem; it creates a secondary failure point that will outlast the original leak. Norken Roofing diagnoses the membrane type, the failure mode, and the correct repair method before any materials are applied.
📞 Call +1-855-302-0688Why Norken Roofing
We identify the specific membrane type and age before proposing any repair. The correct repair method depends entirely on the system in place.
Standing water on a flat roof is a drainage problem before it is a leak. We address slope and drain issues, not just the membrane failure the ponding eventually causes.
We repair TPO with TPO-compatible materials, EPDM with EPDM primers and patches, modified bitumen with matched product. No improvised cross-system repairs.
Every flat roof repair is documented with photos of the failure, the method used, and the materials applied. You get a copy for your maintenance records.
Flat Roof Services
Flat roofs accumulate specific failure modes tied to the membrane system, the drainage design, and the penetration details. Each category of repair requires a different diagnostic approach and a different repair method.
Ponding water -- water that remains on the roof surface 48 hours after a rain event -- is the most structurally serious condition a flat roof can develop, and it is a drainage problem before it is a membrane problem. The weight of standing water adds load to the structural deck and accelerates the deterioration of every membrane type. As the membrane degrades under standing water, it eventually fails, but patching the membrane without correcting the drainage condition means the repaired section will fail again on the same timeline. We assess the drain locations, the interior drain specification and flow capacity, the roof slope (or lack of it) at the problem area, and whether tapered insulation is a practical correction. In cases where the structural deck has deflected and created a permanent low spot, we specify the appropriate fill and regrading approach before any membrane repair is attempted.
TPO membrane is welded at seams using a hot-air welder that fuses the overlapping membrane edges into a single continuous layer. This welded seam is typically the strongest part of a TPO roof when installed correctly, but seam failures occur when the original weld was performed at incorrect temperature or speed, when the membrane was contaminated at the seam interface before welding, or when thermal cycling over time causes separation at an under-welded seam edge. TPO seam repairs require the same hot-air or solvent-weld technique as the original installation -- self-adhesive patches applied over a TPO seam failure are a temporary measure, not a durable repair. We repair TPO seams with manufacturer-approved compatible membrane and welding technique to restore the watertight bond at the seam interface.
EPDM is a rubber-based membrane and it behaves differently from thermoplastic systems like TPO and PVC. EPDM is bonded at seams with lap splice adhesive and seam primer rather than heat welding, and it requires compatible EPDM repair products -- specifically EPDM primer, splice adhesive, and patch material -- for any repair to achieve a durable bond. A repair using silicone caulk or generic roof sealant on an EPDM membrane will not hold for more than a season, because the rubber membrane requires a molecular bond that only EPDM-specific adhesives provide. Puncture repairs, termination bar resealing, and lap seam restoration on EPDM systems require attention to the surface preparation step above all -- contaminated or degraded membrane at the repair location must be cleaned or cut back to a sound surface before any adhesive is applied.
Modified bitumen systems -- the torch-down and cold-applied asphalt membranes common on older commercial and residential flat roofs -- fail at predictable locations: granule loss and surface oxidation in field areas, flashing separation at parapets and penetrations, and blister formation beneath the membrane. Surface oxidation over large field areas is not typically a repair candidate -- it indicates the system is approaching end of service life and replacement is more cost-effective than repeated patching. Discrete failures at flashings and penetrations, however, are very repairable on an otherwise sound modified bitumen system. We repair torch-down systems with compatible torch-applied material and cold-applied systems with matched cold adhesive -- not interchangeable products, because the bonding chemistry is different.
Penetrations -- HVAC curbs, drain bodies, plumbing vents, gas lines, and conduit -- are the most common failure initiation points on any flat roof. The flashing at each penetration must accommodate the movement differential between the rigid penetration element and the flexible membrane, and it must maintain a continuous watertight seal through temperature cycling and UV exposure. Parapet wall flashings are similarly high-risk because they manage the transition between the horizontal roof plane and the vertical wall, where water concentration and wind uplift are highest. We inspect and repair penetration and parapet flashings as the primary focus of our diagnostic assessment on any flat roof leak call in Eldridge -- these are the locations where we find the source of the leak in the majority of cases, regardless of where the interior water stain appeared.
Our Process
We identify the membrane type, assess its overall condition, and locate the failure mode and source -- not just the visible symptom.
We assess drain function and roof slope before membrane repair. Drainage problems that caused the membrane failure are identified and addressed.
Repair materials and methods are matched to the specific membrane system in place -- TPO, EPDM, modified bitumen, or PVC.
Failure location, repair method, and completed repair are documented with photos. Written record provided at completion for your maintenance file.
Reviews
"We had a chronic ponding water problem in one section of our flat commercial roof. Two previous contractors patched the membrane repeatedly but the leak came back every time. Norken Roofing came out and told us the real problem was that the drain in that area was undersized and the roof slope was not directing water to it. They addressed the drain first, then the membrane. We have not had a single issue in 18 months."
"I have an older modified bitumen roof on my garage apartment. The previous contractor used a silicone patch over a seam failure and it lasted one season. Norken Roofing explained that silicone does not bond to modified bitumen and applied a torch-down repair with compatible material. That repair has held through two full winters with no recurrence."
"The diagnostic thoroughness stood out. They walked me through the HVAC curb flashing failure they found, explained exactly why the flashing had separated, and showed me photos before and after the repair. I understood what was wrong and what was fixed -- not just an invoice for services rendered. That level of documentation matters when you manage properties."
FAQ
System-specific membrane repair, drainage assessment, photo documentation. We diagnose the source and fix it correctly. Call +1-855-302-0688.
📞 Call +1-855-302-0688