Portsmouth at a glance
- Postcode districts
- PO1, PO2, PO3, PO4, PO5, PO6
- Population
- about 208,100 (GeoNames)
- Council area
- Portsmouth City Council
- Building approval
- Portsmouth City Council building control, or a registered building control approver
- Nearest main town
- Southampton, about 15 miles
- Guide price region
- South East (+10% on West Midlands rates)
When does a garage roof in Portsmouth need replacing?
Water from a failing garage roof in Portsmouth does not always stay in the garage. On an attached garage it can run down the house wall or track under the flashing, and a blocked or broken gutter can spill onto the drive or a neighbour's property. Replacing the roof deals with the source.
Around Portsmouth, flat roofs are common on low-rise post-war blocks of flats and on 1930s semis with flat-roofed garages and kitchen extensions. Much of the South East sits in the drier Thames catchment at roughly 730 mm of rain a year, so the usual failures are at joints, upstands and outlets rather than from sheer volume of rain.
How much does a new garage roof cost in Portsmouth?
For Portsmouth we use South East rates: £1,750–£3,100 is the guide for a typical 18 m² garage roof in EPDM, VAT included. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Single garage (18 m²), EPDM rubber | £1,750–£3,100 |
| Single garage (18 m²), torch-on felt | £1,650–£2,900 |
| Single garage (18 m²), GRP fibreglass | £1,950–£3,600 |
| Extension (20 m²), GRP, new deck + insulation | £3,300–£5,900 |
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?
- Written workmanship guarantee, with material guarantees registered where available
- Strip-out of old felt, chippings and waste
- Free survey of the deck, fall and gutter line
- New membrane dressed into fresh edge and drip trims
Building regulations in England
Replacing more than half of a flat roof over a heated room usually counts as renovating a thermal element, so the roof is insulated to around 0.16 W/m²K where that's technically and economically feasible, and the work is notified to building control: the council or a registered building control approver, unless a registered competent person self-certifies it. A roof on a new extension is built to 0.15 W/m²K. Patch repairs, and most unheated detached garages, don't trigger the upgrade. Structural changes, or a new covering that adds 15% or more to the roof's weight, also need approval. More on the rules.
Which nearby areas do we also cover?
Garage roofs in Portsmouth: questions
Do you cover Portsmouth?
Yes. Portsmouth is part of our Hampshire coverage, including postcode districts PO1, PO2, PO3, PO4, PO5, PO6. Surveys and roofs are carried out by vetted roofing teams working under S&K Property Investments and Improvement Ltd.
Who checks building regulations for a flat roof in Portsmouth?
Where the work needs approval it goes to Portsmouth City Council building control, or a registered building control approver. We tell you at the survey whether your job needs it and deal with the paperwork as part of the quote.
How much does a new garage roof cost in Portsmouth?
£1,750–£3,100 for a typical 18 m² garage roof in EPDM, at South East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
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.
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.