Gerrards Cross at a glance
- Postcode districts
- SL9
- Population
- about 20,633 (GeoNames)
- Council area
- Buckinghamshire Council
- Building approval
- Buckinghamshire Council building control, or a registered building control approver
- Nearest main town
- Slough, about 6 miles
- Guide price region
- South East (+10% on West Midlands rates)
What does a balcony or terrace in Gerrards Cross need?
Door thresholds are a common reason for balcony work in Gerrards Cross. 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 Gerrards Cross, flat roofs are common on 1930s semis with flat-roofed garages and kitchen extensions and on 1960s and 1970s link-detached houses with flat-roofed garages and porches. 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.
How much does balcony or terrace waterproofing cost in Gerrards Cross?
For Gerrards Cross we use South East rates: £2,100–£3,600 is the guide for a 12 m² balcony in a liquid-applied system including scaffold, VAT included. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Balcony (12 m²), liquid-applied, scaffold | £2,100–£3,600 |
| Single garage (18 m²), EPDM rubber | £1,750–£3,100 |
| Extension (20 m²), GRP, new deck + insulation | £3,300–£5,900 |
How long does it take to waterproof a balcony?
A small balcony is typically waterproofed in two to four working days, plus time for scaffold if it is above ground floor. Liquid and GRP systems need dry weather and cure time between coats, which sets the pace.
The balcony door will be out of use while the membrane is laid and curing, and the room behind may be noisy while old paving or screed is broken out. If the team needs to work through the house, we agree a route and protect floors. Larger terraces with paving or decking take longer, because the finish has to be lifted and reinstated. Resin systems smell while they cure, so nearby windows are best kept closed.
What's included?
- Lifting and setting aside of existing paving or decking
- 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
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?
- Chalfont Saint Peter · 2 mi
- Rickmansworth · 5 mi
- Slough · 6 mi
- Amersham · 6 mi
- Windsor · 7 mi
- Chesham · 8 mi
Balconies and roof terraces in Gerrards Cross: questions
Do you cover Gerrards Cross?
Yes. Gerrards Cross is part of our Buckinghamshire coverage, including postcode districts SL9. 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 Gerrards Cross?
Where the work needs approval it goes to Buckinghamshire 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 Gerrards Cross?
£2,100–£3,600 for a 12 m² balcony in a liquid-applied system including scaffold, at South East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
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.
Why is water coming through the ceiling below my balcony?
The usual causes are a failed door threshold, a blocked or poorly sealed outlet, or a fixing through the membrane. A survey, sometimes lifting paving, finds the source.