Rear Extensions Liverpool

A rear extension is the most straightforward way to add serious living space to your home. By extending out into your back garden, you can transform a cramped kitchen into a spacious open-plan living area, add a ground-floor bedroom, or create a dedicated home office. It’s the single most popular type of extension we build at Glassar Projects, and we’ve completed hundreds of them across Liverpool.

We work right across the city, from the Victorian terraces in Aigburth to the 1930s semis in Allerton, Childwall, and Woolton. Every house is different, and we design every rear extension to suit the property, the street, and most importantly, how your family actually lives.

What Can You Do with a Rear Extension?

The beauty of a rear extension is its flexibility. Here are the most common ways our Liverpool clients use theirs:

Open-plan kitchen-diner: By far the most popular option. We knock through the existing kitchen wall and extend out 4-6 metres to create one large room with bi-fold doors opening onto the garden.
Family living room: If your kitchen is already a good size, a rear extension can give you a second living space, perfect for families with teenagers who need their own area.
Ground-floor bedroom and wet room: For homeowners planning ahead, a rear extension can provide accessible ground-floor living without the need to climb stairs.
Home office: Since 2020, we’ve seen a huge increase in demand for dedicated home offices. A rear extension gives you a proper, separate workspace away from the main house.

How Much Does a Rear Extension Cost in Liverpool?

We’re always upfront about costs. Here’s what a rear extension typically costs in the Liverpool area:

Extension Depth	Typical Cost (inc. VAT)
3 metres	£25,000 – £32,000
4 metres	£30,000 – £38,000
5-6 metres	£35,000 – £45,000

These prices cover everything from foundations to final decoration. For a detailed, fixed-price quote specific to your property, use our Quick Quote Calculator.

Our 4-Step Process

1. Design & Planning

We visit your home, discuss your ideas, and take detailed measurements. Our team then produces drawings and handles the planning application with Liverpool City Council. Many rear extensions fall under Permitted Development, so you may not need full planning permission at all.

2. Foundations & Structure

Our groundwork crew excavates and pours the foundations, then builds the structural walls. Steel beams are installed to support the opening between your existing house and the new extension.

3. Build & Services

The roof goes on, doors and windows are fitted, and our plumbers and electricians run all the first-fix services. Insulation, plastering, and second-fix work follows.

4. Finishing & Handover

We complete all decorating, fit any kitchens or bathrooms, and do a thorough clean. We walk you through the finished space, hand over all certificates and warranties, and make sure you’re completely satisfied.

Permitted Development: How Far Can You Extend?

One of the biggest advantages of a rear extension is that many projects don’t need full planning permission. Under current Permitted Development rules:

Detached houses: You can extend up to 8 metres from the original rear wall (under the Prior Approval scheme) or 4 metres without any notification.
Semi-detached and terraced houses: You can extend up to 6 metres (Prior Approval) or 3 metres without notification.

There are conditions around height, boundary distances, and materials. If your property is in a conservation area or is a listed building, different rules apply. We assess all of this during our initial visit and advise you on the best route.

Neighbourhood Spotlight: Aigburth

Aigburth is one of our busiest areas for rear extensions. The long, narrow Victorian and Edwardian terraces along Aigburth Road and the surrounding streets are perfect candidates for a rear extension that opens up the ground floor. Many of these homes have a separate kitchen, dining room, and living room, all quite small. By extending the kitchen out by 4-5 metres and knocking through to the dining room, you end up with a stunning open-plan space that completely transforms the house. If you’re in Aigburth, we know these houses well and can advise on the best approach for your specific property.

Frequently Asked Questions

1. How far can I extend to the rear without planning permission?

Under Permitted Development, you can typically extend 3 metres from a semi-detached or terraced house, or 4 metres from a detached house, without any notification to the council. Under the Prior Approval scheme, these limits increase to 6 metres and 8 metres respectively.

2. Will a rear extension make the middle of my house dark?

It can if it’s not designed properly. That’s why we always include roof lanterns, skylights, or clerestory windows in our designs. A well-designed rear extension should actually make your home brighter, not darker, by flooding the new space with natural light.

3. Can I have underfloor heating in my rear extension?

Absolutely, and we’d recommend it. Installing underfloor heating during the build is straightforward and relatively inexpensive. It’s much harder and more costly to add later. It works brilliantly with the tiled or engineered wood floors that most clients choose for their new kitchen-diner.

4. How long does a rear extension take to build?

A typical rear extension takes 10-14 weeks from breaking ground to completion. Larger or more complex projects may take 14-18 weeks. We provide a week-by-week schedule before we start.

5. Do I need a Party Wall Agreement?

If your extension is being built up to or on the boundary with your neighbour, you’ll likely need a Party Wall Agreement under the Party Wall Act 1996. This is common for terraced and semi-detached houses in areas like Allerton and Woolton. We can advise you on this and recommend a local surveyor if needed.

6. What happens to my drains?

Many Liverpool homes have drains running along the rear of the property. If your extension is built over existing drains, they may need to be diverted or a build-over agreement obtained from United Utilities. We survey the drainage as part of our initial assessment so there are no surprises.

Related Services

Ready to Extend?

Get a clear, instant estimate with our Quick Quote Calculator, or call us to arrange a free home visit.