Bangor, Gwynedd at a glance
- Postcode districts
- LL57
- Population
- about 18,322 (GeoNames)
- Council area
- Gwynedd Council
- Building approval
- Gwynedd Council building control, or a registered building control approver
- Nearest main town
- Colwyn Bay, about 17 miles
- Guide price region
- Wales (−8% on West Midlands rates)
Why upgrade to a warm roof in Bangor, Gwynedd?
Small commercial buildings in Bangor, Gwynedd with large flat roofs can lose a lot of heat through them. Where the roof is being replaced, upgrading the insulation at the same time is required in most cases and helps reduce running costs for the occupier.
Around Bangor, Gwynedd, flat roofs are common on terraced streets with flat-roofed rear kitchens and bathrooms and on 1930s semis with flat-roofed garages and kitchen extensions. Wales averages roughly 1,460 mm of rain a year, among the wettest in Britain, so we design for steady run-off: proper falls, clear outlets and upstands well above the finished roof.
How much does a warm roof upgrade cost in Bangor, Gwynedd?
At Wales guide rates, a 20 m² extension roof in EPDM with a new deck and insulation comes to £2,600–£4,500 including VAT. 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 | £2,600–£4,500 |
| Extension (20 m²), EPDM with sedum green roof | £4,050–£7,450 |
Can a cold flat roof be converted to a warm roof?
Yes, and it is the usual approach when an older cold roof is re-covered. The old covering is stripped, the deck is checked and replaced where needed, and the vapour control layer, insulation and new waterproofing go on top.
The existing insulation between the joists is assessed at the same time. Leaving it in place can create a cold, unventilated gap that traps moisture, so it is often removed or the build-up is designed so that most of the insulation sits above the deck. We decide this case by case once we can see inside the roof. If the covering is still sound and you are only patching it, the upgrade isn't usually required, and our repair or replace guide explains how to decide between the two.
What's included?
- New waterproofing, with a written workmanship guarantee
- Upstands, trims and kerbs reset to the new roof level
- Survey of the deck, joists and existing insulation
- Vapour control layer on the warm side of the insulation
Building regulations in Wales
The Welsh Approved Document L applies. Renovating more than half of a roof over a heated room means upgrading it to around 0.16 W/m²K where feasible, and new extension roofs are built to 0.13 W/m²K. Welsh Government guidance is that most re-roofing needs building control approval, so check whenever more than a quarter of a roof is replaced or repaired. We deal with the application as part of the job. More on the rules.
Which nearby areas do we also cover?
Warm roof insulation upgrades in Bangor, Gwynedd: questions
Do you cover Bangor, Gwynedd?
Yes. Bangor, Gwynedd is part of our Gwynedd coverage, including postcode districts LL57. 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 Bangor, Gwynedd?
Where the work needs approval it goes to Gwynedd 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 Bangor, Gwynedd?
£2,600–£4,500 for a 20 m² extension roof in EPDM with a new deck and insulation, at Wales guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can you insulate a flat roof from inside instead?
It is possible, but insulating between or under the joists creates a cold roof, which needs ventilation and carries a higher condensation risk. When the roof is being re-covered anyway, a warm roof from above is usually the better option.
Can you add insulation over my existing roof without stripping it?
Sometimes, if the existing covering and deck are dry and sound. We will check at the survey and explain the risks, and our overlay or strip guide covers this choice.