Glass box extensions in Tooting
Thinking about a glass extension for your Tooting home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in TootingFrom £39,000 inc VAT
- PlanningSame limits as single-storey rear; glazing checked for building regs
- Build time10–16 weeks on site
- Postcode districtsCR4, SW12, SW16, SW17, SW19

Planning and approvals in Tooting
In England a glazed or orangery-style extension follows the same size limits as any single-storey rear extension: 3 m or 4 m without an application, or up to 6 m and 8 m through prior approval. Building regulations limit glazing to about a quarter of the new floor area plus the openings it replaces, unless whole-house calculations show the design still performs.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
What we take care of
- Design with specialist glazing input
- Whole-house energy calculations where needed
- Solar-control and low-energy glass specification
- Drainage details for frameless roofs
Solar gain is the risk. We specify solar-control glass, plan for opening vents or sliding panels, and avoid fully glazed roofs on south-facing extensions unless shading is included.
How much does a glass extension cost in Tooting?
Labour and material costs vary across the UK, so for Tooting we use our London factor (×1.3). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Tooting: £3,900 to £7,540 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2 m × 4 m 8 m² | £39,000 – £47,000 | £39,000 – £49,500 | £44,500 – £60,500 |
| 3 m × 4 m 12 m² | £46,500 – £56,500 | £54,500 – £69,000 | £67,000 – £90,500 |
| 3 m × 6 m 18 m² | £70,000 – £84,500 | £81,500 – £103,000 | £100,500 – £136,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
Working in Tooting
Across CR4, SW12, SW16, SW17, SW19, we can visit, measure and advise. We also work in nearby Streatham (1 mile), Mitcham (2 miles), Earlsfield (2 miles), Wimbledon (2 miles).
Just over the Surrey border, Ewell is about 6 miles away. Across London, terraced houses with narrow side returns and tight access are the norm, which shapes everything from party wall notices to how materials reach the back garden.
From first visit to completion
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Your questions about a glass extension in Tooting
How long does a glass extension take to build in Tooting?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
Do you cover all of Tooting?
Yes. We cover Tooting and the surrounding parts of Greater London. Site visits are free and there is no obligation.
Will my neighbours in Tooting be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
How much does a glass extension cost?
Our guide range is about £3,900 to £7,540 per m² including VAT, because structural glass is made to order. A 12 m² standard-spec glass extension is typically £54,500 to £69,000 in Tooting.
Are glass extensions cold in winter?
Modern double or triple glazing with warm-edge spacers and underfloor heating keeps them comfortable. They are not as warm as a solid room, and we explain the trade-off honestly.
Book a free site visit in Tooting
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.