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Crawley, West Sussex

Glazed rear extension in Crawley

Glazed rear extension in Crawley: full-height glass, slim frames and big rooflights for the most open rear room. We measure the house, show you what the rules allow, price it in writing and build it.

We cover Crawley (RH10 and RH11) as part of our West Sussex work. Glass-led rear extensions in Crawley 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 Crawley?

A glazed rear extension in Crawley 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 Crawley
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

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 for a glazed rear extension in Crawley?

Planning for a glazed rear extension in Crawley 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 Crawley like to extend?

Around Crawley the housing ranges from inter-war semis to 1960s and 1970s estates with good-sized gardens. Many of the newer estates had permitted development rights removed by condition, so we check the planning history before anything is drawn.

How a glazed rear extension in Crawley 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. Design and guide price

    Two or three layout options with a guide price for each, so you choose the design knowing what it costs.

  3. Planning and regulations

    We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.

  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 Crawley

Neighbouring places we cover include Broadfield (1.5 miles) and Horley (4.4 miles).

Other work in Crawley:

All rear extensions in Crawley

FAQ

Glazed rear extension questions in Crawley

Is the site visit in Crawley free?

Yes. We visit, measure up and talk through the options with no cost and no obligation.

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.

Sliding or bifold doors?

Sliders give bigger panes and slimmer sightlines; bifolds open the whole width. Our guide compares them.

What postcode areas do you cover around Crawley?

Including RH10 and RH11, and the surrounding West Sussex area.

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

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

How much does a glazed rear extension cost in Crawley?

As a guide, £3,140–£5,380 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £37,500–£64,500 at that rate. Your written price follows the survey.

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.

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