Red flag 1: No site inspection before quoting
A contractor who quotes over the phone without inspecting your roof cannot possibly know the preparation work required. Engineering-grade quotes always follow a physical audit with moisture mapping and crack assessment.
A quote without inspection is a guess—and you will pay for that guess twice.
Red flag 2: No branded materials
The chemistry is the entire product. Legitimate applicators use brands like Dr. Fixit, Fosroc, Sika, Asian Paints or MYK, and can show you batch certificates. Unbranded 'imported' chemicals in unmarked drums are a guarantee of early failure.
Ask for the material brands in writing before you sign anything.
Red flag 3: No written warranty
A stamped, written warranty certificate is the single strongest signal of a professional applicator. It defines scope, duration and what happens if the membrane fails. If a contractor offers only verbal assurances, walk away.
Look for warranty coverage of 5-10 years backed by a named company with a physical address.
The green flags to look for
The right contractor inspects first, recommends a system matched to your slab's condition (not the most expensive option), uses branded chemicals, documents the work, performs a pond test, and hands over a written warranty. That is the standard we hold ourselves to—and the standard you deserve.
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