Letchworth Garden City at a glance
- Postcode districts
- SG6
- Population
- about 33,990 (GeoNames)
- Council area
- North Hertfordshire District Council
- Building approval
- North Hertfordshire District Council building control, or a registered building control approver
- Nearest main town
- Stevenage, about 5 miles
- Guide price region
- East of England (+5% on West Midlands rates)
What does a balcony or terrace in Letchworth Garden City need?
Balconies in Letchworth Garden City are often re-waterproofed when the ceiling below starts to stain. On many older balconies, the membrane was laid under tiles or screed with no way to inspect it, so by the time the leak appears, water may have been tracking under the surface for a long time.
In a town like Letchworth Garden City, flat roofs are commonly found on 1960s and 1970s link-detached houses with flat-roofed garages and porches or shops with flat-roofed rear stores below flats. The East of England is the driest part of Britain, with parts of the Anglian region around 630 mm a year, so summer heat and UV, not rainfall, do most of the ageing on a felt roof.
How much does balcony or terrace waterproofing cost in Letchworth Garden City?
At East of England guide rates, a 12 m² balcony in a liquid-applied system including scaffold comes to £2,000–£3,400 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 | £2,000–£3,400 |
| Single garage (18 m²), EPDM rubber | £1,700–£2,950 |
| Extension (20 m²), GRP, new deck + insulation | £3,150–£5,650 |
Which waterproofing system is best for a balcony?
For most small balconies, a liquid-applied membrane is the practical choice, because it is brushed or rolled on and forms one continuous layer around posts, door frames and outlets with no seams to fail. Many systems include a hard-wearing, anti-slip topcoat.
GRP fibreglass gives a rigid, walkable surface and suits balconies left exposed rather than paved. On larger roof terraces under paving or decking, single-ply membranes are common, and mastic asphalt has a long record on concrete terraces and blocks of flats.
The choice also depends on what goes on top. Paving on pedestals protects the membrane, while an exposed balcony needs a system rated for foot traffic in its own right. We specify the build-up at survey.
What's included?
- Written workmanship guarantee, with approvals handled where needed
- Sealed details at doors, outlets, walls and balustrade posts
- 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?
Balconies and roof terraces in Letchworth Garden City: questions
Do you cover Letchworth Garden City?
Yes. Letchworth Garden City is part of our Hertfordshire coverage, including postcode districts SG6. 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 Letchworth Garden City?
Where the work needs approval it goes to North Hertfordshire District 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 Letchworth Garden City?
£2,000–£3,400 for a 12 m² balcony in a liquid-applied system including scaffold, at East of England guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
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.
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.