Garage roof replacement

Guide price: £1,600–£2,800
Survey: Free for new and replacement roofs
Quote: Fixed, in writing
Coverage: England, Wales, Scotland, NI

What is involved in replacing a garage roof?

Replacing a garage roof means stripping the old felt or sheeting, repairing or renewing the deck, checking the falls and laying a new membrane with fresh edge trims. On a typical single garage, the whole job runs from strip-out to finished roof in sequence.

Strip the old covering and any loose chippings, with waste taken away in a skip.
Check every deck board; chipboard that has swollen or gone soft is replaced with OSB3 or plywood.
Check the fall towards the gutter. Garages often have a single fall to the front or back, and firrings correct it where the joists have sagged.
Insulate only if the garage is, or will become, a heated room.
Lay the membrane, form upstands where the roof meets a wall, and dress it into new drip and edge trims.
Renew the gutter or outlet if the old one is cracked, sagging or too small.

If the fascia boards behind the trims are rotten, we replace them at the same time, priced in the quote rather than added later.

How much does a new garage roof cost?

For an 18 m² single garage on a sound deck, the guide prices below are typical, including VAT; a double garage is usually close to twice the area. Your fixed price follows a free survey.

System	18 m² single garage	Notes
Torch-on felt	£1,500–£2,600	Layered system, usually the lowest cost of the three main options
EPDM rubber	£1,600–£2,800	Often one sheet on a single garage
GRP fibreglass	£1,800–£3,250	Rigid finish, good with gutters and odd shapes
Liquid-applied	£2,050–£3,250	Can suit awkward edges and junctions
Single-ply	£2,050–£3,350	More usual on larger roofs

These figures assume the deck is sound. If boards need replacing, add £20–£35 per m² for the area affected. A new gutter or outlet run is typically £120–£280. Detached garages rarely need scaffold. Put your own size into the guide-price tool, or see the full cost guide.

Which roofing system is best for a garage?

For most single garages, EPDM rubber is a strong choice, because a simple rectangle can usually be covered in one sheet with no joins in the field of the roof. It is light, flexible and quick to lay.

GRP fibreglass suits garages with integral box gutters, several corners or a roof that is walked on to reach windows or clean gutters. Torch-on felt remains a cost-effective, durable option, particularly on larger lock-up runs where budget matters. Where a garage adjoins timber or other combustible material, we also consider whether a torch-free system is the safer method, such as EPDM, GRP or a liquid-applied coating.

If you plan to convert the garage later, say so at survey. A roof built as a warm roof now saves stripping it again when the room is heated.

Do I need planning permission or building regulations for a garage roof?

Usually not for planning, and often not for building regulations either, if the garage is detached and unheated. Re-covering a roof without materially changing its appearance does not normally need a planning application.

An unheated detached garage is not normally a thermal element, so the insulation rules for renovated roofs do not usually apply. That changes if the garage is attached and heated, used as a room, or being converted. A new roof covering that adds 15% or more to the existing weight, or any structural change, still needs building control approval in England. Wales has its own threshold for re-roofing, Scotland works through building standards and NI through district council building control.

Listed buildings and conservation areas can bring extra controls. We confirm what applies at survey and handle approvals where they are needed; our building regulations page covers the detail.

How long does a garage roof replacement take?

A single garage roof is typically finished in one or two days, and a double garage in two or three, weather permitting. Deck repairs and new fascias add time.

Disruption is light. You will need to empty or cover anything stored in the garage, because dust and debris can fall through gaps in an old deck during the strip. The garage door may be out of use for part of the job, and the car is best parked elsewhere so a skip can sit on the drive. We keep the roof weathertight at the end of each day.

What if my garage roof is asbestos cement or old felt?

If your garage has corrugated cement sheets, especially on a pre-2000 building, assume they could contain asbestos until a test says otherwise. We do not remove asbestos; any suspected material is tested and, if confirmed, removed by a licensed specialist before our work starts.

Once the old sheets have gone, the garage usually needs new timber joists or purlins and a deck before a membrane can go on. Old felt garages are more straightforward: the felt is stripped and the deck assessed in the usual way.

Lock-up blocks and rows of garages bring their own issues. A shared roof often has several owners, so we can quote per bay, or for the whole run where everyone agrees, which keeps the edges and joins between garages consistent. Attached garages need careful upstands and flashings where the roof meets the house wall, while detached ones are about edges, gutters and falls.

Not sure whether your roof needs replacing? Our guide to repair or replace sets out the signs.

What's included when we do the work?

Free survey of the deck, fall and gutter line
Strip-out of old felt, chippings and waste
Replacement of soft or swollen deck boards
New membrane dressed into fresh edge and drip trims
Gutter or outlet renewed where the old one has failed
Written workmanship guarantee, with material guarantees registered where available

What do guide prices look like?

Guide prices including VAT at West Midlands rates; regional pages adjust these for your area. The fixed price comes after a free survey for new and replacement roofs.

Job	Guide price inc VAT
Single garage (18 m²), EPDM rubber	£1,600–£2,800
Single garage (18 m²), torch-on felt	£1,500–£2,600
Single garage (18 m²), GRP fibreglass	£1,800–£3,250
Extension (20 m²), GRP, new deck + insulation	£3,000–£5,400

Does anything differ outside England?

Wales: Wales has its own re-roofing rules: check whether approval is needed if more than 25% of the roof is being replaced or repaired. A detached unheated garage is not normally treated as a thermal element.
Scotland: In Scotland, building standards replace building regulations, so check with the council's building standards service whether a warrant is needed. Like-for-like re-covering of an unheated detached garage is often exempt, but structural work or a conversion to a heated room usually needs a warrant.
Northern Ireland: In Northern Ireland, contact the district council's building control before starting work. A heated or converted garage brings the roof under Technical Booklet F1/F2 insulation requirements.

How does the job run from start to finish?

Survey and measure
We look at the roof from above and the deck from inside the garage, then measure and check the fall.
Fixed quote
You receive a written price for the system, any deck boards, trims and gutter work, with no obligation.
Strip and re-cover
The team strips the old roof, repairs the deck and lays the new membrane, usually within one or two days.
Check and hand over
We test the drainage, tidy the site and give you the guarantee paperwork.

Questions about garage roofs

How long does a garage roof last?

It depends on the system. As indicative figures, EPDM lasts 25–50 years, GRP 20–40 and modern torch-on felt 15–25, with good specification and maintenance.

Can a garage roof be replaced in one day?

A small single garage with a sound deck can often be stripped and re-covered in a day. Deck repairs, a double garage or poor weather can stretch it to two or three.

Should I insulate my garage roof?

Only if the garage is heated or you plan to use it as a room. Insulating a cold, unheated garage roof can cause condensation unless it is designed carefully, so we advise case by case.

Can you replace a shared garage roof in a block?

Yes. We can quote for one garage in a row or the whole block, and we take care with the joins between bays so neighbouring roofs stay watertight.

Do I need to empty my garage before the roof is replaced?

It helps to clear valuable or delicate items, and to cover the rest with dust sheets. Debris can fall through gaps in an old deck during strip-out.

Is it worth repairing a garage roof instead?

If the roof is generally sound and dry with one isolated defect, a repair is usually sensible. Widespread cracking, a soft deck or repeat leaks point to replacement.

Can you put a new roof on a garage with a cement sheet roof?

Yes, once any suspected asbestos has been tested and removed by a licensed specialist. The garage then usually needs new timbers and a deck before the new membrane goes on.

What is involved in replacing a garage roof?

How much does a new garage roof cost?

Which roofing system is best for a garage?

Do I need planning permission or building regulations for a garage roof?

How long does a garage roof replacement take?

What if my garage roof is asbestos cement or old felt?

What's included when we do the work?

What do guide prices look like?

Does anything differ outside England?

How does the job run from start to finish?

Survey and measure

Fixed quote

Strip and re-cover

Check and hand over

Questions about garage roofs

Related services

EPDM rubber roofing

GRP fibreglass roofing

Torch-on felt roofing

Flat roof repairs

Where do you offer garage roofs?

Get a fixed price for your flat roof