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.
Browse by topic
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.
Flat Roofing
Guidance on flat roofing.

Budget & Programme
The Commercial Roof Decision Framework
A practical framework for deciding when to repair, when to refurbish and when to replace a commercial roof, based on condition and risk rather than age.
TRS RoofingUpdated 5 Aug 20269 min readRead: The Commercial Roof Decision Framework
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.
