Deeside at a glance
- Postcode districts
- CH5
- Population
- about 32,000 (GeoNames)
- Council area
- Flintshire County Council
- Building approval
- Flintshire County Council building control, or a registered building control approver
- Nearest main town
- Buckley, about 3 miles
- Guide price region
- Wales (−8% on West Midlands rates)
Why upgrade to a warm roof in Deeside?
Many flat-roofed extensions and dormers in Deeside were built with little or no insulation, or with a cold roof that was never properly ventilated. Those rooms are often hard to heat in winter and can suffer condensation, mould and, in time, a rotten deck.
In and around Deeside, flat roofs are typically found on low-rise post-war blocks of flats, and on shops with flat-roofed rear stores below 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.
How much does a warm roof upgrade cost in Deeside?
Guide price in Deeside: £2,600–£4,500 for a 20 m² extension roof in EPDM with a new deck and insulation, 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 |
Will insulating the roof raise its height, and what about doors and upstands?
Yes. A warm roof makes the roof thicker, often by more than 100 mm depending on the insulation and the U-value target. That extra height is the main thing we plan around.
Waterproofing at a wall usually needs to rise about 150 mm above the finished roof surface, so if the roof gets higher, the upstand has to go higher too. That can be a problem where the roof meets a door threshold, a low window sill, a cavity tray or a rooflight kerb. At the edges, trims and fascias are reset to the new level, and gutters may need to move.
Where there isn't enough height, the options include using thinner, higher-performance insulation, lowering the deck where the structure allows, raising the sill or threshold, or, where it is genuinely not feasible to reach the full target, insulating as far as is reasonable and recording why with building control. We work this out at the survey so there are no surprises on the day.
What's included?
- Vapour control layer on the warm side of the insulation
- New waterproofing, with a written workmanship guarantee
- Survey of the deck, joists and existing insulation
- Rigid insulation boards sized to the U-value target
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 Deeside: questions
Do you cover Deeside?
Yes. Deeside is part of our Flintshire coverage, including postcode districts CH5. 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 Deeside?
Where the work needs approval it goes to Flintshire County 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 Deeside?
£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.
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.
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.