Lambeth at a glance
- Postcode districts
- SW9, SW2, SW4, SE24, SW8, SW12, SE21, SE27 and 1 more
- Council area
- London Borough of Lambeth
- Building approval
- London Borough of Lambeth building control, or a registered building control approver
- Guide price region
- London (+20% on West Midlands rates)
What does a balcony or terrace in Lambeth need?
Settled, rocking or cracked paving is a common reason to re-waterproof a terrace in Lambeth. Slabs bedded directly on the membrane can damage it over time. Relaying them on adjustable pedestals protects the waterproofing and gives a level surface that drains underneath.
In and around Lambeth, flat roofs are typically found on mansion blocks and purpose-built flats with large flat roofs, and on kitchen extensions and roof terraces behind period houses. The Thames basin is one of the drier parts of Britain at roughly 730 mm of rain a year, but summer heat is the bigger test here: dark membranes on south-facing roofs swing a long way in temperature.
How much does balcony or terrace waterproofing cost in Lambeth?
At London guide rates, a 12 m² balcony in a liquid-applied system including scaffold comes to £2,300–£3,900 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 | £2,300–£3,900 |
| Single garage (18 m²), EPDM rubber | £1,900–£3,350 |
| Extension (20 m²), GRP, new deck + insulation | £3,600–£6,450 |
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?
- Strip-out of the failed membrane and deck repairs
- Free survey of the deck, falls, outlets and door thresholds
- Sealed details at doors, outlets, walls and balustrade posts
- 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?
- Southwark · 2 mi
- Wandsworth · 4 mi
- Westminster · 4 mi
- Lewisham · 4 mi
- Kensington and Chelsea · 4 mi
- Camden · 5 mi
Balconies and roof terraces in Lambeth: questions
Do you cover Lambeth?
Yes. Lambeth is part of our London coverage, including postcode districts SW9, SW2, SW4, SE24, SW8, SW12 and 3 more. 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 Lambeth?
Where the work needs approval it goes to London Borough of Lambeth 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 Lambeth?
£2,300–£3,900 for a 12 m² balcony in a liquid-applied system including scaffold, at London guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Is a roof terrace heavier than a normal flat roof?
Yes. Paving, people, planters and furniture all add load, so a structural engineer should confirm the roof can carry it before a terrace is formed.
Do you install balustrades?
Our work is the waterproofing and drainage. We detail the membrane around balustrade fixings so they stay watertight, and we can advise on where posts should be fixed.