- Guide price
- £2,600–£4,550
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
County Durham at a glance
- Largest towns
- Darlington, Hartlepool, Stockton-on-Tees, Durham
- Postcode areas
- DH, DL, SR, TS
- Building control
- Darlington Borough Council, Hartlepool Borough Council, Stockton-on-Tees Borough Council and 1 other council
- Neighbouring areas
- Tyne and Wear · Northumberland · North Yorkshire · Cumbria
- Guide price region
- North East (−7% on West Midlands rates)
How much does a warm roof upgrade cost in County Durham?
Guide prices including VAT at North 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 | £2,600–£4,550 |
| Extension (20 m²), EPDM with sedum green roof | £4,100–£7,500 |
Which flat roofs are common in County Durham?
Flat roofs in County Durham sit on 1930s semis with flat-roofed garages and kitchen extensions, bungalows with flat-roofed side extensions and dormers and 1960s and 1970s link-detached houses with flat-roofed garages and porches. England averages roughly 870 mm of rain a year; the North East is drier than the west but cold and windy near the coast, so wind uplift and freeze-thaw are in the specification. Approximate 1991–2020 regional averages based on Met Office data.
Building regulations in England
Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. Renovated roofs over heated rooms are insulated to around 0.16 W/m²K where that's feasible, and new extension roofs are built to 0.15 W/m²K. In County Durham the application goes to Darlington Borough Council, Hartlepool Borough Council, Stockton-on-Tees Borough Council and 1 other council. More on the rules.
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.
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 County Durham do we cover?
- Darlington
- Hartlepool
- Stockton-on-Tees
- Durham
- Chester-le-Street
- Billingham
- Stanley
- Consett
- Newton Aycliffe
- Bishop Auckland
- Seaham
- Peterlee
- Spennymoor
Warm roof insulation upgrades in County Durham: questions
Which towns in County Durham do you cover?
All of County Durham. 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 County Durham?
£2,600–£4,550 for a 20 m² extension roof in EPDM with a new deck and insulation, at North East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Which council handles building control for a flat roof in County Durham?
It depends on where the roof is: in County Durham that's Darlington Borough Council, Hartlepool Borough Council, Stockton-on-Tees Borough Council and 1 other council. Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. We confirm which applies at the survey.
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.
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.
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.
Everything about warm roof insulation upgrades → · All flat roofing in County Durham →
