- Guide price
- £2,600–£4,500
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
Isle of Anglesey at a glance
- Largest towns
- Holyhead
- Postcode areas
- LL
- Building control
- Isle of Anglesey County Council
- Neighbouring areas
- Gwynedd · Conwy · Denbighshire · Flintshire
- Guide price region
- Wales (−8% on West Midlands rates)
How much does a warm roof upgrade cost in Isle of Anglesey?
Guide prices including VAT at Wales 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 | £2,600–£4,500 |
| Extension (20 m²), EPDM with sedum green roof | £4,050–£7,450 |
Which flat roofs are common in Isle of Anglesey?
Flat roofs in Isle of Anglesey sit on 1930s semis with flat-roofed garages and kitchen extensions, bungalows with flat-roofed side extensions and dormers and low-rise post-war blocks of flats. 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. Approximate 1991–2020 regional averages based on Met Office data.
Building regulations in Wales
Welsh guidance is that most re-roofing needs building control approval, so it's worth checking whenever more than a quarter of a roof is replaced or repaired. Renovated roofs are upgraded to around 0.16 W/m²K where feasible, and new extension roofs are built to 0.13 W/m²K under the Welsh Approved Document L. In Isle of Anglesey the application goes to Isle of Anglesey County Council. More on the rules.
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.
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.
Which towns in Isle of Anglesey do we cover?
Warm roof insulation upgrades in Isle of Anglesey: questions
Which towns in Isle of Anglesey do you cover?
All of Isle of Anglesey. The main towns have their own pages below, and if yours isn't listed we still cover it: send your postcode and we'll confirm.
How much does a warm roof upgrade cost in Isle of Anglesey?
£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.
Which postcode areas do you cover in Isle of Anglesey?
All of Isle of Anglesey, including the LL postcode areas. Send your full postcode and we'll confirm.
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.
Will a warm roof make my room warmer?
Usually, yes. A room under a poorly insulated flat roof loses less heat once the roof is upgraded and tends to feel more even in temperature. How much difference you notice depends on how the roof was built before.
Is a warm roof worth it on a garage?
On a detached, unheated garage, usually not, as there is no heated space to protect and the thermal rules don't normally apply. On an integral or heated garage, or one being converted into a room, it is.
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