Dorchester at a glance
- Postcode districts
- DT1
- Population
- about 16,879 (GeoNames)
- Council area
- Dorset Council
- Building approval
- Dorset Council building control, or a registered building control approver
- Nearest main town
- Poole, about 20 miles
- Guide price region
- South West (+3% on West Midlands rates)
What does a balcony or terrace in Dorchester need?
Door thresholds are a common reason for balcony work in Dorchester. Where a door was fitted with a low step-out and no drainage channel, water driven against the frame finds its way under the sill. Re-waterproofing gives the chance to rebuild that detail properly.
Around Dorchester, flat roofs are common on bungalows with flat-roofed side extensions and dormers and on terraced streets with flat-roofed rear kitchens and bathrooms. 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.
How much does balcony or terrace waterproofing cost in Dorchester?
Guide price in Dorchester: £1,950–£3,350 for a 12 m² balcony in a liquid-applied system including scaffold, including VAT at South West rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Balcony (12 m²), liquid-applied, scaffold | £1,950–£3,350 |
| Single garage (18 m²), EPDM rubber | £1,650–£2,900 |
| Extension (20 m²), GRP, new deck + insulation | £3,100–£5,550 |
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?
- Free survey of the deck, falls, outlets and door thresholds
- Written workmanship guarantee, with approvals handled where needed
- Strip-out of the failed membrane and deck repairs
- Lifting and setting aside of existing paving or decking
Building regulations in England
Replacing more than half of a flat roof over a heated room usually counts as renovating a thermal element, so the roof is insulated to around 0.16 W/m²K where that's technically and economically feasible, and the work is notified to building control: the council or a registered building control approver, unless a registered competent person self-certifies it. A roof on a new extension is built to 0.15 W/m²K. Patch repairs, and most unheated detached garages, don't trigger the upgrade. Structural changes, or a new covering that adds 15% or more to the roof's weight, also need approval. More on the rules.
Which nearby areas do we also cover?
- Weymouth · 7 mi
- Yeovil · 18 mi
- Poole · 20 mi
- Wimborne Minster · 20 mi
- Ferndown · 24 mi
- Bournemouth · 24 mi
Balconies and roof terraces in Dorchester: questions
Do you cover Dorchester?
Yes. Dorchester is part of our Dorset coverage, including postcode districts DT1. 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 Dorchester?
Where the work needs approval it goes to Dorset 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 Dorchester?
£1,950–£3,350 for a 12 m² balcony in a liquid-applied system including scaffold, at South West guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can I put decking straight onto my flat roof?
Not directly onto the membrane. Decking needs a supporting system that spreads the load and lets water drain, and the roof must be checked for the extra weight.
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.