Essex
Glazed and glass-box rear extensions in Essex
Full-height glass, slim frames and big rooflights for the most open rear room. We design and build rear extensions across Essex, from Southend-on-Sea and Basildon to Colchester, covering single-storey kitchen extensions, two-storey additions, side returns and wraparounds.
If your garden in Southend-on-Sea faces south, expect us to talk about overhangs and solar-control glass before frame colours. Essex mixes Victorian terraces with 1930s semis, so both side returns and full-width kitchen extensions suit houses here.
How much does a glazed rear extension cost in Essex?
A glazed rear extension in Essex is priced at £2,970–£5,090 per square metre including VAT as a guide, before kitchen fit-out and fees. East of England prices run slightly above our West Midlands baseline; clay soils near trees are the main foundation variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £35,500–£61,000 |
| 4 m wide × 6 m deep (24 m²) | £71,000–£122,000 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission in Essex?
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part 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.
Where in Essex do we work?
- Southend-on-Sea
- Basildon
- Colchester
- Chelmsford
- Harlow
- Grays
- Braintree
- Brentwood
- Clacton-on-Sea
- South Benfleet
- Canvey Island
- Billericay
- Rayleigh
- Stanford-le-Hope
- Wickford
- Witham
- Pitsea
- Maldon
- Waltham Abbey
- South Ockendon
- Harwich
- Hadleigh
- Walton-on-the-Naze
- Frinton-on-Sea
- Rochford
- Saffron Walden
- Tilbury
- Chafford Hundred
- Chigwell
- Halstead
- Buckhurst Hill
- Epping
FAQ
Questions people ask
Will a glass extension be too hot?
Not if it is designed for its orientation, with solar-control glass, shading and ventilation.
Is there a limit on how much glass I can have?
In England the simple rule is 25% of the floor area plus openings removed; more is allowed with a calculation showing the house still meets Part L.
Sliding or bifold doors?
Sliders give bigger panes and slimmer sightlines; bifolds open the whole width. Our guide compares them.
Do you cover all of Essex?
We cover 32 towns and districts in Essex, including Southend-on-Sea, Basildon and Colchester.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.