- Price per m²
- £67–£118
- Typical life
- 25–50 years
- Manufacturer guarantees
- 20-year material warranties are common
- Typical garage roof
- £1,650–£2,900
Dorset at a glance
How much does an EPDM rubber roof cost in Dorset?
Guide prices including VAT at South West rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Single garage (18 m²), EPDM rubber | £1,650–£2,900 |
| Extension (20 m²), EPDM, new deck + insulation | £2,900–£5,050 |
| Porch or bay (4 m²), EPDM | £750–£1,300 |
Which flat roofs are common in Dorset?
Flat roofs in Dorset sit on terraced streets with flat-roofed rear kitchens and bathrooms, bungalows with flat-roofed side extensions and dormers and low-rise post-war blocks of flats. 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. 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 Dorset the application goes to BCP Council and Dorset Council. More on the rules.
Do I need building regulations approval to replace a roof with EPDM?
Often, yes. In England, Wales and Northern Ireland, re-covering more than half of a flat roof over a heated room usually counts as renovating a thermal element, so the roof should be insulated towards the renovation standard where that is feasible; in Scotland, the council's building standards service decides whether a building warrant is needed.
An unheated detached garage normally falls outside these rules, and a patch repair is treated differently from a full re-cover.
In practice that means a warm roof: insulation above the deck, a vapour control layer beneath it and the EPDM on top. The extra thickness lifts the finished roof, so at survey we check door thresholds, window cills, wall flashings and upstand heights, aiming for an upstand of about 150 mm above the finished surface. Where approval is needed, we deal with building control or building standards for you. The building regulations page and our warm vs cold roof guide go into more detail.
How are the joins, edges and upstands made watertight on an EPDM roof?
They are bonded with contact adhesive and sealed with purpose-made EPDM tapes and pre-formed pieces, because the edges and details are where most rubber roof leaks start.
- Wall upstands: the rubber is turned up the wall, usually to about 150 mm above the finished roof, fully bonded, then finished with a termination bar or a cover flashing chased into the masonry.
- Corners: folded rather than cut where possible, or finished with pre-formed pieces.
- Joins: on roofs wider than one sheet, the laps are cleaned, primed and joined with splice tape, then rolled firmly.
- Pipes and vents: sealed with pre-formed pipe boots rather than relying on mastic.
- Edges and outlets: drip and kerb trims are fixed and the junction with the membrane is sealed with cover tape; outlets are bonded into the membrane at the lowest point.
We also check the falls before laying, because standing water around an outlet shortens the life of any detail. There is more on this in our pages on edges and drainage and rooflight upstands.
Which towns in Dorset do we cover?
EPDM rubber roofing in Dorset: questions
Which towns in Dorset do you cover?
All of Dorset. 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 an EPDM rubber roof cost in Dorset?
£1,650–£2,900 for a typical 18 m² garage roof in EPDM, at South West guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Which postcode areas do you cover in Dorset?
All of Dorset, including the BH, DT postcode areas. Send your full postcode and we'll confirm.
Can a punctured EPDM roof be repaired?
Usually, yes. The area is cleaned and primed, then an EPDM patch or cover tape is bonded over the damage. If water has reached the deck, a survey first is sensible.
Does an EPDM roof need maintenance?
Very little. Clear leaves from outlets and gutters, look over trims and upstands once or twice a year and after storms, and keep foot traffic to a minimum.
Can EPDM be laid over an old felt roof?
Sometimes, but we usually recommend stripping old felt first. Overlaying hides any rot or wet insulation underneath, and over a heated room a full replacement is often when insulation has to be added anyway.
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