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Blackburn, Lancashire

Glazed rear extension in Blackburn

For homes in Blackburn, a glazed rear extension is often the simplest way to gain space without moving. Full-height glass, slim frames and big rooflights for the most open rear room. We take it from survey to completion certificate.

Blackburn and its postcode districts BB1, BB2 and BB3 are part of our Lancashire coverage. If your garden in Blackburn 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 Blackburn?

For Blackburn we work from the North West England rate: £2,630–£4,510 per square metre of new floor, including VAT, standard specification. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.

Glazed rear extension prices in Blackburn
SizeGuide price inc VAT
3 m wide × 4 m deep (12 m²)£31,500–£54,000
4 m wide × 6 m deep (24 m²)£63,000–£108,500

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 Blackburn?

Here is how the rules in England apply to a glazed rear extension in Blackburn.

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. 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 Blackburn like to extend?

Stone and brick terraces are common around Blackburn. Where houses back onto a ginnel or alley, deliveries can come in from the rear, which makes the build tidier.

How a glazed rear extension in Blackburn comes together

  1. 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.

  2. Drawings and budget

    Floor plans and elevations for the options, each with a guide price.

  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 Blackburn

Close by, we work in Darwen, about 3.7 miles away, and Great Harwood, about 3.9 miles away.

Other work in Blackburn:

All rear extensions in Blackburn

FAQ

Glazed rear extension questions in Blackburn

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.

How long does a rear extension take to build in Blackburn?

Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.

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.

How much does a glazed rear extension cost in Blackburn?

As a guide, £2,630–£4,510 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £31,500–£54,000 at that rate. Your written price follows the 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.

Can you match the brick or stone on my Blackburn 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.

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