Balconies and roof terraces across East Sussex

Guide price

£2,100–£3,600

Survey

Free for new and replacement roofs

Quote

Fixed, in writing

Coverage

England, Wales, Scotland, NI

How much does balcony or terrace waterproofing cost in East Sussex?

Guide prices including VAT at South East rates. The fixed price comes after a free survey for new and replacement roofs.

Which flat roofs are common in East Sussex?

Flat roofs in East Sussex sit on terraced streets with flat-roofed rear kitchens and bathrooms, bungalows with flat-roofed side extensions and dormers and shops with flat-roofed rear stores below flats. Much of the South East sits in the drier Thames catchment at roughly 730 mm of rain a year, so the usual failures are at joints, upstands and outlets rather than from sheer volume of rain. Approximate 1991–2020 regional averages based on Met Office data.

Building regulations in England

Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. Renovated roofs over heated rooms are insulated to around 0.16 W/m²K where that's feasible, and new extension roofs are built to 0.15 W/m²K. In East Sussex the application goes to Brighton & Hove City Council, Eastbourne Borough Council, Hastings Borough Council and 3 other councils. More on the rules.

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.

How are thresholds, drainage and paving handled on a terrace?

They are designed together, because most balcony leaks start at the door threshold, a blocked outlet or a fixing driven through the membrane. Getting those three right matters more than the brand of membrane.

Thresholds: upstands are usually 150 mm above the finished surface, but a level or low step-out door cannot always achieve that. Where the upstand has to be reduced, extra protection is needed, such as a drainage channel at the door and a fall away from it, and the membrane must still run up and under the door sill.

Drainage: every terrace needs a reliable way off for water, with outlets sized for the area and an overflow if one outlet could block. Outlets under paving need access for cleaning.

Inverted roofs and pedestals: on an inverted roof the insulation sits above the waterproofing and is held down by paving or ballast, protecting the membrane from sun and foot traffic. Adjustable pedestals lift paving slabs level above the falls, so water drains underneath and the surface stays flat. Balustrade posts are fixed through upstands or side-fixed where possible, with every penetration sealed into the membrane.

Which towns in East Sussex do we cover?

• Brighton
• Eastbourne
• Hastings
• Bexhill-on-Sea
• Hailsham
• Seaford
• Rottingdean
• Crowborough
• Portslade
• Peacehaven
• Uckfield
• Lewes

Everything about balconies and roof terraces → · All flat roofing in East Sussex →