A flat roof at the end of its life does not necessarily need to be replaced. Professional flat roof coating — applying a waterproof protective coating over the existing surface — can extend the roof’s functional life significantly at a fraction of replacement cost.

Types of Flat Roof We Coat

Felt flat roofs — the most common type on UK domestic properties. As felt ages, it becomes brittle, cracks and fails at laps and flashings. A liquid waterproof coating applied over the existing felt provides a seamless, fully waterproof membrane.
GRP (fibreglass) flat roofs — GRP cracks and crazes over time. Coating restores waterproofing without replacement.
EPDM (rubber) roofs — where seams or flashings have failed, coating repairs can address localised issues.
Asphalt flat roofs — oxidised asphalt can be recoated to restore waterproofing and extend life.

How Much Does Flat Roof Coating Cost?

Flat roof coating typically costs £20–£40 per square metre depending on the product, condition of the existing roof and access requirements. This compares to £50–£150 per square metre for flat roof replacement.

For a typical garage flat roof (25m²), coating costs £500–£1,000 versus £1,250–£3,750 for replacement.

How Long Does Flat Roof Coating Last?

A professionally applied flat roof coating lasts 10-20 years depending on the product system and the condition of the existing roof. Most products carry a manufacturer’s guarantee.