Knotty Ash, Merseyside
Glazed rear extension in Knotty Ash
We plan and build glazed and glass-box rear extensions for homeowners in Knotty Ash. Full-height glass, slim frames and big rooflights for the most open rear room. Start with a free site visit, then a written price once the design is agreed.
We cover Knotty Ash (L13, L14 and L16) as part of our Merseyside work. If your garden in Knotty Ash 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 Knotty Ash?
A glazed rear extension in Knotty Ash is priced at £2,630–£4,510 per square metre including VAT as a guide, before kitchen fit-out and fees. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Size | Guide 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 |
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 Knotty Ash?
Here is how the rules in England apply to a glazed rear extension in Knotty Ash.
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. 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 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 glazed rear extension in Knotty Ash comes together
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.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
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.
Glazed rear extensions near Knotty Ash
We also build glazed and glass-box rear extensions in nearby Old Swan (0.5 miles) and West Derby (1.3 miles).
- Glazed rear extension in Old Swan
- Glazed rear extension in West Derby
- Glazed rear extension in Childwall
- Glazed rear extension in Wavertree
- Glazed rear extension in Norris Green
Other work in Knotty Ash:
FAQ
Glazed rear extension questions in Knotty Ash
Is the site visit in Knotty Ash free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
How much does a glazed rear extension cost in Knotty Ash?
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.
Will a glass extension be too hot?
Not if it is designed for its orientation, with solar-control glass, shading and ventilation.
How long does a rear extension take to build in Knotty Ash?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
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 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.