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Knotty Ash, Merseyside

Two-storey rear extension in Knotty Ash

Two-storey rear extension in Knotty Ash: a larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. We measure the house, show you what the rules allow, price it in writing and build it.

Knotty Ash sits in Merseyside, with postcode districts including L13, L14 and L16. In Knotty Ash, a two-storey rear extension is worth comparing with the cost of moving once stamp duty, agents' and legal fees are counted.

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 two-storey rear extension cost in Knotty Ash?

Guide prices for a two-storey rear extension in Knotty Ash start from our North West England rate of £1,690–£2,540 per square metre, including VAT. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.

Two-storey rear extension prices in Knotty Ash
SizeGuide price inc VAT
3 m × 5 m footprint, two floors (30 m²)£51,000–£76,000
4 m × 6 m footprint, two floors (48 m²)£81,000–£122,000

Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.

Do you need planning permission for a two-storey rear extension in Knotty Ash?

Here is how the rules in England apply to a two-storey rear extension in Knotty Ash.

A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.

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 Knotty Ash like to extend?

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

How a two-storey rear extension in Knotty Ash comes together

  1. Survey visit

    We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.

  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. Fixed price and build

    A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.

Two-storey rear extensions near Knotty Ash

Close by, we work in Old Swan, about 0.5 miles away, and West Derby, about 1.3 miles away.

Other work in Knotty Ash:

All rear extensions in Knotty Ash

FAQ

Two-storey rear extension questions in Knotty Ash

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.

How much does a two-storey rear extension cost in Knotty Ash?

As a guide, £1,690–£2,540 per square metre including VAT for a standard specification. For example, 3 m × 5 m footprint, two floors (30 m²): about £51,000–£76,000 at that rate. Your written price follows the survey.

Can it be built on a terraced house?

Sometimes, but the upper floor is harder to get through planning on a terrace because of the effect on neighbours. A single-storey extension with a loft conversion is often an easier route.

Do I need planning permission for a rear extension in Knotty Ash?

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.

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.

Can you match the brick or stone on my Knotty Ash 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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