- 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
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 mastic asphalt roofing 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 |
|---|---|
| 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 Isle of Anglesey?
Flat roofs in Isle of Anglesey sit on bungalows with flat-roofed side extensions and dormers, 1930s semis with flat-roofed garages and kitchen extensions and terraced streets with flat-roofed rear kitchens and bathrooms. 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.
Is mastic asphalt still a good choice, or should I switch systems?
Mastic asphalt is still a good choice on concrete roofs, heritage and older buildings, and roofs that carry heavy foot traffic or plant. On lightweight timber roofs, garages and most modern extensions, another system is usually more practical.
Benefits: very long typical life; jointless and fully bonded; takes foot traffic well, especially with a paving finish; matches the original roof on many older buildings; local repairs blend into the existing surface.
Drawbacks: heavy, so the structure must be able to carry it; higher cost; needs specialist labour and hot works with molten material; can crack in cold if not well maintained, and softens in strong sun without a reflective finish.
If the structure is lightweight or the budget tight, torch-on felt or EPDM are common replacements. A compatible liquid-applied system can sometimes be laid over sound asphalt. On larger roofs, single-ply may be considered, and GRP suits smaller roofs needing a hard finish. Our repair or replace guide helps with the decision.
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 Isle of Anglesey do we cover?
Mastic asphalt roofing 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 mastic asphalt roofing cost in Isle of Anglesey?
£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 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.
Is mastic asphalt the same as tarmac?
No. Both contain bitumen, but mastic asphalt is a dense, voidless mix with fine limestone aggregate, made to be fully waterproof, while road surfacing is a different material.
Can I repair a mastic asphalt roof myself?
Not properly. Lasting asphalt repairs use fresh hot asphalt, which needs specialist equipment, training and hot-works control. Cold-applied sealants can hold a small leak for a short time, but they are a stopgap until a specialist repair.
Can you put felt or rubber over an asphalt roof?
Sometimes, if the asphalt is dry, well bonded and sound, using a compatible system and primer. Liquid membranes are a common choice because they bond well to cleaned asphalt.
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