Where modified bitumen fits
Modified bitumen is asphalt reinforced with polyester or fiberglass and modified with rubber or plastic, applied in two or more plies with a granulated cap sheet on top. It handles foot traffic well and shows up on many older commercial buildings, schools and churches.
- Roof repair$650–$3,800Typical repair, per job
- Roof coating$3.50–$10/sq ftPer sq ft, depends on roof size
- Roof inspectionFreeInspection and estimate at no cost
Prices checked October 2026. Every proposal is one all-inclusive price: permits and sales tax built in.
How it goes down
We install modified bitumen two ways:
- Torch-applied. The sheets are heated to bond. Fast and durable, with strict fire precautions on every job.
- Self-adhered. Peel-and-stick sheets with no open flame, for roofs where a torch isn’t a good idea.
Which one we recommend depends on the building, the deck and what’s around the roof.
Repair, coat or replace?
- Repair when the damage is local: blisters, open laps, failed flashing.
- Coat when the roof is aging but still bonded and free of blisters. Conklin’s Membrane Coating System is approved over aged modified bitumen in that condition. See roof coatings.
- Replace when wet insulation or failed plies cover a large share of the roof. Many owners replace with TPO.
What it costs
Typical repairs run $650 to $3,800. Coatings on sound roofs typically run $3.50 to $10 per square foot. Replacements are quoted per project after a free inspection.
Payment and warranty
Roofs we contract directly with a building owner are typically billed 75% at signing and 25% on completion. When we’re the subcontractor for a general contractor, we bill through the GC’s pay-application process. You can pay through the online invoice link, by check or in cash.
Our one-year workmanship warranty starts at substantial completion and covers problems from our installation, not normal wear and tear, damage by others or weather. Membrane and material defects fall under the manufacturer’s warranty, which passes through to you.
Contacted White Rock Construction about checking our roof for possible leaks. He came out the same day and checked it out. After sealing some holes he told us it was probably wind that blew up some shingles allowing the rain to come in. Friendly and honest service.
Great experience. They were professional and attentive. They were able to get to us very timely and did a great job. The entire process went smooth! I would recommend them for any construction needs.
Epic crew and responsive. Highly recommend!
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Modified bitumen questions
Should I replace my mod bit roof with mod bit or TPO?
It depends on foot traffic, the deck and your budget. We’ll price both when both make sense.
Can you coat my old modified bitumen roof?
If it’s still bonded and free of blisters, often yes.
Do you work in Illinois?
No. We don’t hold an Illinois roofing license, so all of our roofing is in Indiana.
Need a roof inspected or priced for your building?
Send us a few details and Doug Stoliby, our sales manager, will contact you within one business day to discuss your goals, answer questions and schedule a site visit.
Doug Stoliby, Sales ManagerDoug will reach out within 1 business day.