Rear extension design, approvals and build across the UKCall 0800 088 6341 · Online guide price
Rear Extensionsrear-extensions.co.uk 0800 088 6341 Get a guide price

Barnham, West Sussex

Glazed rear extension in Barnham

Full-height glass, slim frames and big rooflights for the most open rear room. We design, get the approvals for and build glazed and glass-box rear extensions in Barnham and the surrounding area, with one contract from the first survey to building control sign-off.

Barnham sits in West Sussex, with postcode districts including BN18 and PO22. A wide sliding door with one long rooflight, rather than a fully glazed roof, keeps a glass-led extension usable in summer.

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 Barnham?

A glazed rear extension in Barnham is priced at £3,140–£5,380 per square metre including VAT as a guide, before kitchen fit-out and fees. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.

Glazed rear extension prices in Barnham
SizeGuide 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

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 Barnham?

The planning route for a glazed rear extension in Barnham is set by England's householder rules and your council.

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. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.

What are homes in Barnham like to extend?

Barnham has a mix of Victorian terraces near the centre and larger Edwardian and inter-war houses further out. Clay soils across much of the South East mean deeper foundations near trees, which we plan for at the survey.

How a glazed rear extension in Barnham comes together

  1. 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.

  2. Options and costs

    We draw layout options and price each one, so the budget shapes the design rather than surprising you later.

  3. Approvals

    Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.

  4. 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 Barnham

Neighbouring places we cover include Bognor Regis (3.9 miles) and Littlehampton (4.5 miles).

Other work in Barnham:

All rear extensions in Barnham

FAQ

Glazed rear extension questions in Barnham

Do I need planning permission for a rear extension in Barnham?

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 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.

What postcode areas do you cover around Barnham?

Including BN18 and PO22, and the surrounding West Sussex area.

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.

Can you match the brick or stone on my Barnham house?

We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.

Next step

See what your rear extension would cost

Get a guide price online in a couple of minutes, or book a free site visit and we'll measure up and talk you through the planning route.

CallGuide price