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Flat roof systems

Torch-on felt roofing in Mountain Ash

For blocks of flats, shops and houses in Mountain Ash, torch-on felt remains a practical way to re-roof at a sensible cost. Each job follows the same pattern: survey, written quote, strip and lay, then a fire watch and a walk-round with you before we hand over the written workmanship guarantee.

Roofer torching a slate-grey mineral cap sheet on a commercial flat roof behind edge protectionComputer-generated example image

Mountain Ash at a glance

Postcode districts
CF45
Population
about 11,230 (GeoNames)
Council area
Rhondda Cynon Taf County Borough Council
Building approval
Rhondda Cynon Taf County Borough Council building control, or a registered building control approver
Nearest main town
Rhondda, about 3 miles
Guide price region
Wales (−8% on West Midlands rates)

Why choose torch-on felt roofing in Mountain Ash?

Where a flat roof in Mountain Ash already has a felt covering and the building owner wants like-for-like, torch-on is the natural replacement. The old roof is stripped, the deck checked and the new layers laid, often with warm-roof insulation added when the space below is heated.

In a town like Mountain Ash, flat roofs are commonly found on low-rise post-war blocks of flats or 1930s semis with flat-roofed garages and kitchen extensions. 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 torch-on felt roof cost in Mountain Ash?

Guide price in Mountain Ash: £1,400–£2,400 for a typical 18 m² garage roof in torch-on felt, including VAT at Wales rates. The fixed price comes after a free survey for new and replacement roofs.

JobGuide price inc VAT
Single garage (18 m²), torch-on felt£1,400–£2,400
Extension (20 m²), felt, new deck + insulation£2,500–£4,300
Block of flats (150 m²), felt + insulation + scaffold£14,300–£25,000
Single garage (18 m²), EPDM rubber£1,450–£2,600
Extension (20 m²), EPDM, new deck + insulation£2,600–£4,500

Is torch-on roofing safe, and what is the difference between two- and three-layer systems?

Yes, torch-on is safe when hot works are properly controlled, because most roof fires linked to torching start at hidden timber or debris near edges and upstands, not on the open roof. Our teams follow a hot-works routine on every job:

  • check eaves, fascias, soffits and wall cavities for timber, nests and debris before lighting a torch;
  • use a cold-applied or self-adhesive membrane, rather than a flame, at edges, against combustible materials and in tight details;
  • keep fire extinguishers on the roof and the gas bottles secured and away from the work;
  • stop torching well before the team leaves, then carry out a fire watch so smouldering is spotted while people are still on site.

As for layers, a two-layer system (underlay plus cap sheet) is common on domestic roofs such as garages and extensions. A three-layer system adds an intermediate sheet, giving more thickness and redundancy, and is often specified on larger, commercial and multi-occupied roofs. The right choice depends on the size and use of the roof and the system's requirements, so we set it out in the quote.

Near a boundary, the external fire performance of the tested build-up, such as a BROOF(t4) classification, can also matter, and we check it where it applies.

What's included?

  • Vapour control layer and warm-roof insulation where needed
  • Strip-off of the existing roof covering and removal of waste
  • Hot-works checks and fire watch on every torch-on job
  • Mineral-finished cap sheet, upstands, outlets and edge trims

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?

Torch-on felt roofing in Mountain Ash: questions

Do you cover Mountain Ash?

Yes. Mountain Ash is part of our Rhondda Cynon Taf coverage, including postcode districts CF45. 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 Mountain Ash?

Where the work needs approval it goes to Rhondda Cynon Taf County Borough 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 torch-on felt roof cost in Mountain Ash?

£1,400–£2,400 for a typical 18 m² garage roof in torch-on felt, at Wales guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.

Is torch-on felt better than the old felt roofs?

Yes, considerably. Modern torch-on membranes are polymer-modified and polyester-reinforced, laid in bonded layers, and typically last much longer than the older felt systems they replace.

Is torch-on suitable for a block of flats?

Yes, layered bitumen systems are widely used on blocks of flats and commercial buildings. Larger roofs often use three layers and insulation, with hot works planned around residents.

Other flat roof work in Mountain Ash

Torch-on felt roofing in Mountain Ash: get a fixed price

Free survey and a written fixed quote for replacement and new roofs. No obligation.

Call usGet a guide price