Bournemouth at a glance
- Postcode districts
- BH1, BH2, BH3, BH4, BH5, BH6, BH7, BH8 and 3 more
- Population
- about 163,600 (GeoNames)
- Council area
- BCP Council
- Building approval
- BCP Council building control, or a registered building control approver
- Guide price region
- South West (+3% on West Midlands rates)
Why upgrade to a warm roof in Bournemouth?
Kitchen extensions in Bournemouth, as elsewhere, produce a lot of moisture from cooking. Under a cold flat roof, that moisture can condense on the deck. A warm roof keeps the deck warm and puts a vapour control layer in the way, which lowers the risk considerably.
In and around Bournemouth, flat roofs are typically found on terraced streets with flat-roofed rear kitchens and bathrooms, and on lock-up garage blocks on estates. The South West averages roughly 1,260 mm of rain a year and many roofs face wind off the Atlantic, so we specify fixings and edge details for wind uplift as well as drainage.
How much does a warm roof upgrade cost in Bournemouth?
For Bournemouth we use South West rates: £2,900–£5,050 is the guide for a 20 m² extension roof in EPDM with a new deck and insulation, VAT included. 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 | £2,900–£5,050 |
| Extension (20 m²), EPDM with sedum green roof | £4,550–£8,350 |
How long does a warm roof last?
The insulation in a warm roof should last for the life of the waterproofing above it, as long as it stays dry. Rigid PIR boards don't settle or slump in the way some loose insulation can.
The waterproofing is what sets the timescale. EPDM is typically quoted at 25 to 50 years, GRP at 20 to 40 years and modern torch-on felt at 15 to 25 years with good specification and care. A warm build-up also helps the deck, because keeping it warm and dry lowers the risk of condensation rot. If the waterproofing fails and water gets into the insulation, the wet boards should be replaced, so leaks need prompt attention. The lifespan guide compares the systems.
What's included?
- Building control or building standards handled where needed
- New waterproofing, with a written workmanship guarantee
- Upstands, trims and kerbs reset to the new roof level
- Rigid insulation boards sized to the U-value target
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?
- Christchurch · 4 mi
- Poole · 5 mi
- Ferndown · 6 mi
- Wimborne Minster · 6 mi
- New Milton · 10 mi
- Totton · 22 mi
Warm roof insulation upgrades in Bournemouth: questions
Do you cover Bournemouth?
Yes. Bournemouth is part of our Dorset coverage, including postcode districts BH1, BH2, BH3, BH4, BH5, BH6 and 5 more. 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 Bournemouth?
Where the work needs approval it goes to BCP 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 warm roof upgrade cost in Bournemouth?
£2,900–£5,050 for a 20 m² extension roof in EPDM with a new deck and insulation, at South West guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
How thick does flat roof insulation need to be?
It depends on the insulation product and the U-value target. With common PIR boards, meeting a renovation target usually means well over 100 mm. Thinner, higher-performance boards are available where height is tight.
Does a warm roof stop condensation?
It greatly reduces the risk by keeping the deck warm and placing a vapour control layer on the warm side. Good ventilation in kitchens and bathrooms below still helps.
