Newhaven, East Sussex
Glazed rear extension in Newhaven
Thinking about a glazed rear extension in Newhaven? Full-height glass, slim frames and big rooflights for the most open rear room. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Newhaven is covered from our East Sussex round, including BN9. If your garden in Newhaven 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 Newhaven?
In Newhaven, our guide for a glazed rear extension is £3,140–£5,380 per square metre including VAT for a standard specification. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £37,500–£64,500 |
| 4 m wide × 6 m deep (24 m²) | £75,500–£129,000 |
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 Newhaven?
Planning for a glazed rear extension in Newhaven follows the English householder rules.
English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres 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. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Newhaven like to extend?
Commuter semis and detached houses make up much of Newhaven, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How a glazed rear extension in Newhaven comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Glazed rear extensions near Newhaven
We also build glazed and glass-box rear extensions in nearby Seaford (2.7 miles) and Peacehaven (2.7 miles).
- Glazed rear extension in Seaford
- Glazed rear extension in Peacehaven
- Glazed rear extension in Rottingdean
- Glazed rear extension in Lewes
- Glazed rear extension in Brighton
Other work in Newhaven:
FAQ
Glazed rear extension questions in Newhaven
Do I need planning permission for a rear extension in Newhaven?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
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.
Is a glass box a conservatory?
No. It is built to Building Regulations as part of the house, with insulated floor and roof, so it is usable all year.
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 you match the brick or stone on my Newhaven house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
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.