Glass box extensions across Pinner
Our design and build teams take on glass extensions in Pinner, from the first measured survey through planning and building control to the finished room.
- Guide price in PinnerFrom £39,000 inc VAT
- PlanningSame limits as single-storey rear; glazing checked for building regs
- Build time10–16 weeks on site
- Postcode districtsHA2, HA5

Is a glass extension right for your house?
- Garden-facing dining rooms
- Small infill spaces and side returns
- Period and listed-style houses where a light touch is wanted
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 Pinner?
For Pinner we adjust our national guide rates by ×1.3, the factor we use for London. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Pinner: £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 |
For a figure based on your own dimensions, use our guide-price tool.
Covering Pinner
Across HA2, HA5, we can visit, measure and advise. We also work in nearby Wealdstone (2 miles), Ruislip (2 miles), Harrow (2 miles), South Ruislip (3 miles).
For homes towards Hertfordshire, Bushey is around 4 miles away. London's housing is dominated by Victorian and Edwardian terraces, many with a rear outrigger and a side return, and 1930s semis in the outer boroughs. Conservation areas are common, so the planning check comes first.
Will the council need to approve it?
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.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
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).
Our process, step by step
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
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
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 Pinner
How long does a glass extension take to build in Pinner?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
Will my neighbours in Pinner 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.
Do you cover all of Pinner?
Yes. We cover Pinner and the surrounding parts of Greater London. Site visits are free and there is no obligation.
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 Pinner.
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 Pinner
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.