Commercial roofing knowledge and technical guidance.
Written for the people who have to make the decision: surveyors, estates and facilities teams, and building owners. Guidance on diagnosing roof defects, choosing between repair, coating, overlay, over-clad and replacement, and planning works on buildings that stay in use.
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Start from the decision you are making.
Work out what the roof needs
Guidance on surveys, defect diagnosis and the choice between repair, coating, overlay, over-clad and replacement.
Plan budget, programme and disruption
How commercial roof works are costed, sequenced and delivered on buildings that stay in use.
Guarantees, safety and long-term performance
What guarantees actually cover, how roof access is made safe, and how energy or solar work affects the roof.
Ask TRS Technical
A specific question? Ask the TRS technical team.
Have a question about a commercial roof, proposed refurbishment or technical detail? Submit it to the TRS technical team for practical guidance.
- · General guidance may be anonymised and published with permission.
- · Project-specific advice may require a roof survey or further assessment.
- · Submitting a question does not constitute a design, specification or quotation.
Guarantees & Compliance
Guidance on guarantees & compliance.
Roof Surveys & Defects
Commercial roof guarantees explained
Clear explanation of product guarantees, insurance-backed guarantees, metal coating guarantees and single-point guarantees that cover workmanship. Practical guidance for surveyors and estates managers.
TRS RoofingUpdated 31 Jul 20266 min readRead: Commercial roof guarantees explained
Flat Roofing
Overlay or strip on commercial flat roofs: how to decide
When a commercial flat roof is approaching the end of its serviceable life, the first question is almost always the same: can we overlay, or do we need to strip back to the deck?
TRS RoofingUpdated 27 Jul 2026Read: Overlay or strip on commercial flat roofs: how to decide
Guidance by sector
Roofing guidance by building type.
Speak to TRS
Start with a free initial roof survey
Send a brief description of the building and roof. The initial roof survey and site visit are free of charge, and a member of the TRS team will be in touch to arrange it.