Sidcup, Greater London
Glazed rear extension in Sidcup
Full-height glass, slim frames and big rooflights for the most open rear room. If you live in Sidcup and want to know what a glazed rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
Sidcup is covered from our Greater London round, including BR7, DA14 and DA15. If your garden in Sidcup faces south, expect us to talk about overhangs and solar-control glass before frame colours.
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 Sidcup?
In Sidcup, our guide for a glazed rear extension is £3,640–£6,240 per square metre including VAT for a 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 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a glazed rear extension in Sidcup?
Planning for a glazed rear extension in Sidcup follows the English householder rules.
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 Sidcup like to extend?
Sidcup is mostly 1930s semis, short terraces and post-war houses, so full-width single-storey and two-storey rear extensions are realistic on many plots. Some later estates had permitted development rights removed by condition, so we check the planning history first.
How a glazed rear extension in Sidcup comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
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 Sidcup
Close by, we work in Chislehurst, about 1.6 miles away, and Bexley, about 2.2 miles away.
- Glazed rear extension in Chislehurst
- Glazed rear extension in Bexley
- Glazed rear extension in Welling
- Glazed rear extension in Eltham
- Glazed rear extension in Bickley
Other work in Sidcup:
FAQ
Glazed rear extension questions in Sidcup
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.
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.
Does glass need planning permission?
The same rules apply as any rear extension; glass does not change the depth or height limits.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
How long does a rear extension take to build in Sidcup?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
How much does a glazed rear extension cost in Sidcup?
As a guide, £3,640–£6,240 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £43,500–£75,000 at that rate. Your written price follows the survey.