Treharris at a glance
- Postcode districts
- CF46
- Population
- about 12,352 (GeoNames)
- Council area
- Merthyr Tydfil County Borough Council
- Building approval
- Merthyr Tydfil County Borough Council building control, or a registered building control approver
- Nearest main town
- Rhondda, about 6 miles
- Guide price region
- Wales (−8% on West Midlands rates)
What does a balcony or terrace in Treharris need?
Owners of flats in Treharris sometimes find that a neighbour's balcony is leaking into their home. Where a balcony serves one flat but sits over another, the repair needs proper waterproofing and drainage, and a clear written specification helps everyone involved agree the work.
Treharris's flat roofs are mostly on shops with flat-roofed rear stores below flats, with plenty on terraced streets with flat-roofed rear kitchens and bathrooms too. 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 balcony or terrace waterproofing cost in Treharris?
At Wales guide rates, a 12 m² balcony in a liquid-applied system including scaffold comes to £1,750–£3,000 including VAT. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Balcony (12 m²), liquid-applied, scaffold | £1,750–£3,000 |
| Single garage (18 m²), EPDM rubber | £1,450–£2,600 |
| Extension (20 m²), GRP, new deck + insulation | £2,750–£4,950 |
Do I need planning permission for a balcony or roof terrace?
For a new balcony or roof terrace, generally yes. In England, balconies and raised platforms are not permitted development for houses, so a planning application is normally needed, and the other nations have their own rules.
Re-waterproofing an existing, approved balcony that looks the same afterwards does not normally need planning. Building regulations are a separate question. A terrace over a heated room is a thermal element, so replacing most of it can bring insulation requirements and approval. Turning a flat roof into a terrace also raises structural questions, because people, furniture and paving add load, and it needs guarding, such as a balustrade, that meets the regulations. A structural engineer should confirm that the roof can carry the new use.
Listed buildings and conservation areas add another layer of control. Our building regulations page covers approvals, and our planning permission guide covers the planning side.
What's included?
- Written workmanship guarantee, with approvals handled where needed
- Free survey of the deck, falls, outlets and door thresholds
- Strip-out of the failed membrane and deck repairs
- Lifting and setting aside of existing paving or decking
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?
Balconies and roof terraces in Treharris: questions
Do you cover Treharris?
Yes. Treharris is part of our Merthyr Tydfil coverage, including postcode districts CF46. 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 Treharris?
Where the work needs approval it goes to Merthyr Tydfil 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 balcony or terrace waterproofing cost in Treharris?
£1,750–£3,000 for a 12 m² balcony in a liquid-applied system including scaffold, at Wales guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
What is an inverted roof terrace?
It is a terrace where the insulation sits above the waterproofing, held down by paving or ballast. The membrane stays protected and at a steadier temperature.
Can you waterproof a balcony without lifting the tiles?
Sometimes a liquid system can go over a sound, well-bonded surface, but if water is already getting under the tiles they usually have to come up.