Harrow on the Hill, Greater London
Glazed rear extension in Harrow on the Hill
We plan and build glazed and glass-box rear extensions for homeowners in Harrow on the Hill. Full-height glass, slim frames and big rooflights for the most open rear room. Start with a free site visit, then a written price once the design is agreed.
Harrow on the Hill and its postcode districts HA1, HA2 and HA3 are part of our Greater London coverage. Glass-led rear extensions in Harrow on the Hill are planned around which way the garden faces, because that decides the glass specification.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a glazed rear extension cost in Harrow on the Hill?
For Harrow on the Hill we work from the London rate: £3,640–£6,240 per square metre of new floor, including VAT, standard specification. London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £43,500–£75,000 |
| 4 m wide × 6 m deep (24 m²) | £87,500–£150,000 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a glazed rear extension in Harrow on the Hill?
Here is how the rules in England apply to a glazed rear extension in Harrow on the Hill.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
New fabric must meet Approved Document L (2021 edition incorporating 2023 amendments): walls 0.18, roof 0.15 and floor 0.18 W/m²K, windows 1.4 W/m²K or Band B. Under the simple route, new windows, doors and rooflights should not exceed 25% of the extension floor area plus any openings removed; more glass is possible with a whole-house calculation.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Harrow on the Hill like to extend?
Much of Harrow on the Hill is 1920s and 1930s semis and short terraces with longer gardens than inner London, which suit full-width single-storey rear extensions. Parking suspensions, skip licences and controlled hours on residential streets shape the programme more than the build itself.
How a glazed rear extension in Harrow on the Hill comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Glazed rear extensions near Harrow on the Hill
From Harrow on the Hill, the nearest places we also cover are Harrow (0.5 miles) and Sudbury (1.2 miles).
- Glazed rear extension in Harrow
- Glazed rear extension in Sudbury
- Glazed rear extension in Headstone
- Glazed rear extension in Wealdstone
- Glazed rear extension in Wembley
Other work in Harrow on the Hill:
FAQ
Glazed rear extension questions in Harrow on the Hill
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
Do you handle building control in Harrow on the Hill?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Does glass need planning permission?
The same rules apply as any rear extension; glass does not change the depth or height limits.
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.