- Price per m²
- £78–£138
- Typical life
- 30–60 years
- Manufacturer guarantees
- 15-year material, up to 25-year system guarantees
- 30 m² roof
- £3,200–£5,750
Merthyr Tydfil at a glance
- Largest towns
- Merthyr Tydfil, Treharris
- Postcode areas
- CF
- Building control
- Merthyr Tydfil County Borough Council
- Neighbouring areas
- Rhondda Cynon Taf · Blaenau Gwent · Caerphilly · Torfaen
- Guide price region
- Wales (−8% on West Midlands rates)
How much does mastic asphalt roofing cost in Merthyr Tydfil?
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 |
|---|---|
| Mastic asphalt roof (30 m²), scaffold | £3,200–£5,750 |
| Localised patch repair | £140–£460 |
| Single garage (18 m²), EPDM rubber | £1,450–£2,600 |
| Extension (20 m²), EPDM, new deck + insulation | £2,600–£4,500 |
Which flat roofs are common in Merthyr Tydfil?
Flat roofs in Merthyr Tydfil sit on lock-up garage blocks on estates, bungalows with flat-roofed side extensions and dormers and 1960s and 1970s link-detached houses with flat-roofed garages and porches. 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 Merthyr Tydfil the application goes to Merthyr Tydfil County Borough Council. More on the rules.
How long does mastic asphalt last, and what guarantees are available?
Mastic asphalt is one of the longest-lasting flat roof systems, typically giving 30 to 60 years with good specification and maintenance. Many older asphalt roofs are still watertight decades after they were laid.
Age does show eventually. Common signs include crazing and cracking from sun exposure, blisters where moisture has been trapped beneath, splits at skirtings where the building has moved, and ponding where the deck has settled. Regular maintenance, such as renewing solar reflective paint, keeping outlets clear and repairing cracks early, makes a real difference to life.
Material and system guarantees are available on some specified asphalt systems, and we register them for you where the system allows. Every re-roof carries our written workmanship guarantee, with the length set out in the quote, and insurance-backed options can be discussed. Our lifespan guide compares asphalt with the other systems.
What building regulations apply when an asphalt roof is replaced?
Replacing more than half of an asphalt roof over a heated space usually counts as renovating a thermal element in England, Wales and Northern Ireland, so the roof should be insulated towards the renovation standard where technically and economically feasible; Scottish owners should check with the local authority's building standards service whether the work needs a warrant.
On older buildings, adding insulation can be constrained by parapet heights, door thresholds and the character of the building, and the regulations allow for what is technically feasible. In England, a new covering that adds 15% or more to the roof's weight also needs approval, so a switch to heavier asphalt is checked against the structure. Listed buildings may need listed building consent for changes to their character. We deal with building control or building standards where needed; see the building regulations page.
Which towns in Merthyr Tydfil do we cover?
Mastic asphalt roofing in Merthyr Tydfil: questions
Which towns in Merthyr Tydfil do you cover?
All of Merthyr Tydfil. 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 mastic asphalt roofing cost in Merthyr Tydfil?
£3,200–£5,750 for a 30 m² mastic asphalt roof including scaffold, at Wales 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 Merthyr Tydfil?
It depends on where the roof is: in Merthyr Tydfil that's Merthyr Tydfil County Borough Council. 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. We confirm which applies at the survey.
Why are mastic asphalt roofs painted silver or white?
The reflective coating keeps the asphalt cooler in sun, reducing softening and slowing the surface ageing that leads to crazing. It usually needs renewing every few years as part of maintenance.
Is mastic asphalt suitable for a balcony or terrace?
Yes, asphalt is traditionally used on terraces and walkways because it takes foot traffic well, often with paving on top. A new balcony or terrace generally needs planning permission, so check before converting a roof.
How heavy is a mastic asphalt roof?
Considerably heavier than felt, rubber or single-ply, which is why it is usually laid on concrete or strong timber decks. We check the structure before recommending asphalt on any roof.
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