Garage Roof Replacement Cost UK (2026 Prices)

Garage Roof Replacement Costs by Material and Size

The biggest variable is material choice. These are installed costs (materials, labour, waste removal) for a standard single or double garage with straightforward access.

These prices assume the roof deck (OSB or plywood) is sound. If the deck needs replacing — common when felt has been leaking — add £300 to £700 depending on area. Your roofer should inspect the deck after stripping the old covering and quote separately for any deck work found.

Torch-On Felt: Still the Most Common Choice

Felt remains the default for many quotes because it is the cheapest upfront. A competent three-layer torch-on felt installation will last 10 to 15 years with luck. Budget two-layer installations may fail in seven or eight.

The problem with felt is cumulative. Most homeowners who chose felt the first time choose EPDM or GRP the second time — after experiencing the repairs, the callbacks and the ceiling damp. Over a 30-year period, two felt installations plus two to three repair jobs frequently cost more in total than a single EPDM installation would have.

Felt is still a reasonable choice for: a garage you plan to demolish in the next 10 to 15 years, a rental property with a tight maintenance budget, or as a temporary covering while a larger project is planned. For anything else, the long-term economics are not in its favour.

EPDM Rubber: The Best Long-Term Value

EPDM (ethylene propylene diene monomer) is a single-ply rubber membrane bonded to the deck in a single sheet. Brands like Firestone RubberCover and ClassicBond dominate the UK market. It is the most widely recommended upgrade from felt because the lifespan-to-cost ratio is by far the strongest of the three options.

Why EPDM beats felt over time: A single EPDM installation at £1,200 for a standard garage will outlast two felt installations that each cost £900 — and with none of the leak repairs in between. The payback period on the premium over felt is typically seven to ten years on a roof that will then last another 20 to 40 more.

What to check when specifying EPDM:

• Ask for a named product (ClassicBond, Firestone, RENOLIT) — not just "rubber roofing"
• Confirm the installer is a registered installer for that brand — this is required for the full manufacturer guarantee
• Ask whether the adhesive bonding or mechanical fastening system is included
• Upstands (where the membrane turns up against walls) are the primary failure point — ask how these are detailed and what sealant system is used

GRP Fibreglass: The Premium Option

GRP (glass reinforced polyester) is applied as liquid resin and chopped glass mat, curing to a rigid, seamless shell. It is the premium flat roof solution for garages, and justifies its cost when the installation is done correctly.

The "when done correctly" qualification matters. GRP is installation-sensitive. Applied in cold or damp conditions, or where the installer rushes pot life or applies insufficient mat layers, it will crack or delaminate within a few years. This is why GRP has a mixed reputation — it is not the material that fails, it is poor installation.

For a garage, GRP makes particular sense when:

• The roof has an attached area (lean-to, lobby, car port) with a more complex shape that benefits from a seamless system
• You want a walkable surface (GRP with correct topcoat is foot-traffic rated)
• Appearance matters — GRP can be coloured and has a clean, uniform finish
• You want the longest possible guarantee from an approved installer

Always check that the installer is Approved Installer status for their brand system. The 20 to 25-year guarantees offered by manufacturers like Bauder and Sika are only valid through approved installers.

Asbestos in Pre-2000 Garage Roofs

Any garage roof installed before 2000 could contain asbestos cement sheeting. This is particularly common in garages built in the 1960s, 1970s and 1980s, where corrugated asbestos cement roofing was widely used.

Asbestos cement sheeting in good condition is not immediately dangerous — it only poses a risk when fibres become airborne (when drilled, cut or broken). But removal must still follow the Control of Asbestos Regulations 2012, even for non-licensed material.

What this means in practice:

• A licensed contractor is required for any work on roofs containing more than 0.1% asbestos by weight — this covers most pre-2000 asbestos cement
• Non-licensed removal (for some lower-risk materials) still requires the contractor to notify the local HSE office 14 days before starting work
• Disposal must be at a licensed hazardous waste facility
• The asbestos survey, removal and disposal adds £300 to £800 on top of the standard replacement price

If you are unsure whether your garage roof contains asbestos, a survey from an accredited asbestos surveyor costs £150 to £250 and provides a written report. Do not disturb the material to investigate — if in doubt, treat it as asbestos until confirmed otherwise.

What Affects Your Quote

The price range for the same material on the same size garage varies more than people expect. These are the main drivers:

• Deck condition — the roof deck that the membrane sits on may need full or partial replacement. This is only known after stripping. Ask for a price with and without deck replacement so you are not surprised.
• Access — a detached garage in an open garden is simple. A garage integrated into a terrace with restricted side access, or against a boundary, requires more effort and cost. Scaffolding to protect a neighbour's property may be needed.
• Existing drainage — is there a working downpipe and gutter? Falls (the slope of the roof towards drainage) adequate? Poor drainage is a common cause of flat roof failure and should be corrected during replacement, not ignored.
• Location — labour rates in London and the South East run 20 to 30 percent above Midlands and northern England averages.
• Integral vs detached — an integral garage (within the house footprint) may trigger Part L building regulations if any insulation work is involved. A detached standalone garage is generally outside the building regulations scope for a straightforward re-roof.

Repair vs Full Replacement

The decision is simpler for garage roofs than for pitched roofs because flat felt is all-or-nothing: individual repairs on felt that has reached end of life keep failing in new places. You seal one joint and the next one opens.

Repair makes sense when:

• The roof is less than five years old and has a localised failure at a specific joint or upstand
• The felt is otherwise sound and the failure is a single point event (debris impact, foot traffic damage)
• The deck is sound and no widespread moisture is present

Replace the whole roof when:

• The felt is blistering across a significant area
• You have had more than one repair in the last three years
• The felt is over 12 to 15 years old and you are being asked to repair it
• Any investigation reveals wet or delaminated deck

A repair on an old felt roof costs £150 to £400 and buys, on average, two to three winters before the next failure. Three repair jobs at £250 each equals £750 spent — plus the frustration and the risk of ceiling damage in between. At that point you are spending most of the cost of a new EPDM roof with none of the benefit. Most experienced roofers will tell you this honestly if you ask.