Worthing at a glance
- Postcode districts
- BN11, BN12, BN13, BN14
- Population
- about 113,866 (GeoNames)
- Council area
- Worthing Borough Council
- Building approval
- Worthing Borough Council building control, or a registered building control approver
- Nearest main town
- Brighton, about 10 miles
- Guide price region
- South East (+10% on West Midlands rates)
What makes a good extension roof in Worthing?
Rooflights fitted after the roof was built are a frequent source of trouble in Worthing extensions. If the kerb was not formed properly or the membrane was simply sealed around the frame, leaks follow. Replacing the roof is the chance to rebuild every upstand to a proper standard.
Worthing's flat roofs are mostly on low-rise post-war blocks of flats, with plenty on bungalows with flat-roofed side extensions and dormers too. 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 extension roof cost in Worthing?
Guide price in Worthing: £3,100–£5,350 for a 20 m² extension roof in EPDM with a new deck and insulation, including VAT at South East rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Extension (20 m²), EPDM, new deck + insulation | £3,100–£5,350 |
| Extension (20 m²), GRP, new deck + insulation | £3,300–£5,900 |
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £3,300–£5,750 |
| Single garage (18 m²), EPDM rubber | £1,750–£3,100 |
How long will my kitchen be disrupted by a new roof?
Most single-storey extension roofs are replaced in two to four working days, depending on size, rooflights and weather. The kitchen usually stays in use throughout.
Expect noise during the strip-out, and occasional dust through gaps around old rooflights, so it helps to cover worktops and move anything fragile off high shelves. We strip only what we can make weathertight by the end of each day. If a rooflight or lantern is being lifted and refitted, there may be a temporary cover over the opening for a short time. Resin systems smell while they cure, so keep the windows below the roof closed on that day.
What's included?
- Free survey of the roof, abutment and room below
- Falls set away from the house wall
- New deck, vapour control layer and warm-roof insulation
- New abutment upstand and flashing, plus rebuilt rooflight kerbs
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?
- Lancing · 2 mi
- Shoreham-by-Sea · 5 mi
- Portslade · 7 mi
- Littlehampton · 7 mi
- Brighton · 10 mi
- Bognor Regis · 14 mi
Extension and kitchen roofs in Worthing: questions
Do you cover Worthing?
Yes. Worthing is part of our West Sussex coverage, including postcode districts BN11, BN12, BN13, BN14. 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 Worthing?
Where the work needs approval it goes to Worthing Borough 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 extension roof cost in Worthing?
£3,100–£5,350 for a 20 m² extension roof in EPDM with a new deck and insulation, at South East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Will a new extension roof sit higher than the old one?
Usually, by the thickness of the added insulation. We check the height against the upstairs window sills, door thresholds and wall flashings at survey so everything still works.
How do I know my extension roof needs replacing rather than repairing?
Repeated leaks, a soft deck, wet insulation or widespread cracking point to replacement. A single defect on a dry, sound roof can usually be repaired.