Why refurbish an aged metal roof?

June 10, 2025

If your metal roof is aged and exhibiting early stages of delamination or corrosion, you need to act.

But should you install new metal sheets? Or should you recoat the existing roof with today’s coatings technologies?

This article is intended to guide you through the decision, clearly setting out the benefits and drawbacks of each option.


Modern high-performance coating systems, with rust inhibiting properties, are often the lowest cost, but an over-sheet is the only option if the existing roof sheets have extensive rust and perforations.



High Performance Coating


Benefits:

  • Cost may be claimed under decorations covenant
  • Warranty up to 25 years
  • Increased market value
  • Lower cost than an over-sheet
  • Building can still be actively used during the process
  • Less disruption and noise during installation than over-sheet

Drawbacks:

  • No change to thermal performance


The costs to apply a new coating to the roof can often be recovered in dilapidation claims under decorations covenants



Over-Sheet


Benefits:

  • Improved thermal performance
  • Increased market value
  • Warranty 25+ years
  • Building can still be actively used during the process

Drawbacks:

  • More disruption and noise during installation compared to coating
  • Higher cost than a coating
  • Weight approx 10kg per sq metre – needs structural engineer


Over-sheet is the only option if the existing roof sheets have extensive rust and perforations