House Extension Types
Not sure which type of house extension is right for your property? This complete guide covers every type of extension available to London and Hertfordshire homeowners — with costs, planning rules and which property types each one suits best. LCCL Construction designs and builds all types. LABC Award Winners 2024. Over 200 reviews rated 4.7 out of 5.
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Which Extension Is Right for Your Home?
Choosing the right type of house extension depends on your property, your budget and what you want to achieve. This guide covers every type of house extension available to homeowners in London and Hertfordshire, with costs, planning considerations and which property types each extension suits best.
LCCL Construction is an award-winning design and build company based in Finchley, London N3. We design and build all types of house extensions across London and Hertfordshire. With over 20 years of experience, 200+ reviews rated 4.7/5 and LABC Awards Regional Winners 2024, we can advise on the best extension for your property.
Please note: Every project is bespoke and individually designed to suit your property. All costs are indicative and subject to final architectural drawings, structural engineer calculations, finishing specification, project location, size and scope of works, any additional alterations, surveys and party wall agreements. A detailed written quote will be provided following your consultation.
1
Rear House Extension
Extends from the back of the property. The most common type of extension in London. Suits terraced, semi-detached and detached houses. Typically 3 to 6 metres deep. Most fall under permitted development rights, so planning permission is usually not required. Costs: £35,000 to £80,000 for full design and build.
2
Side Return Extension
Infills the narrow alley along the side of the house. Very popular on Victorian and Edwardian terraced houses across London. Widens the kitchen and creates open-plan layouts. The glass roof over the side return is a signature feature that floods the space with light. Costs: £35,000 to £55,000.
3
Wraparound Extension
Combines rear and side return extensions into an L-shaped addition. Maximises ground floor space by extending both backwards and along the side. Ideal for terraced houses with a side return and rear garden. Often the best option for creating the largest possible open-plan kitchen-diner-living area. Costs: £60,000 to £100,000.
4
Side Extension
Extends from the side of a semi-detached or detached house. Adds significant floor area on properties with wide plots. Can accommodate an additional reception room, utility, downstairs bedroom or garage conversion. Often requires planning permission. Costs: £50,000 to £90,000.
5
Rear and Side Extension
Combines a rear extension with a full side extension for maximum ground floor space. Best suited to semi-detached and detached properties with available land to the side. Can add 30 to 50 square metres of floor area. Costs: £55,000 to £100,000.
6
Double-Storey Extension
Extends the house over two floors, adding both ground floor and first floor space simultaneously. Requires planning permission in most cases. Significantly increases the size of the property and is the most cost-effective way to add large amounts of space. Estimated Depending Costs: £80,000 to £350,000 and very large homes can cost more.
7
Kitchen Extension
A rear or wraparound extension specifically designed around creating a large open-plan kitchen-diner. The most popular and highest value-adding type of extension in London. Incorporates bi-fold doors, skylights and roof lanterns for maximum natural light. Costs: £40,000 to £100,000.
8
Loft Conversion and Extension Combined
Combines a loft conversion with a ground floor extension in a single project. Maximises space at both levels — extra bedrooms and bathrooms upstairs, enlarged kitchen and living areas downstairs. Saves 10% to 15% compared to doing them separately. Costs: £70,000 to £150,000.
Which Extension Is Right for Your Home?
Frequently Asked Questions
What is the cheapest type of house extension?
The cheapest type of house extension is a side return extension or small rear extension, both starting from around £35,000 in London for full design and build. Side return extensions are particularly cost-effective on Victorian terraced houses.
Which type of extension adds the most value?
Open-plan kitchen extensions and combined loft conversion and extension projects add the most value. Kitchen extensions typically add 10% to 15% to property value, while combined projects can add 20% to 30%.
Which Extension Is Right for Your Home?
The best way to find out which extension suits your property is to book a free consultation with LCCL Construction. Our architect will assess your home, discuss your requirements and recommend the best option to maximise your space and budget. Call 020 8037 7332 or visit lcclconstruction.co.uk.
Which extension is best for a terraced house?
Rear extensions, side return extensions and wraparound extensions all work well on terraced houses. If your property has a side return, a wraparound gives you the most space. If not, a rear extension is the best option.
Which extension is best for a semi-detached house?
Semi-detached houses can benefit from rear extensions, side extensions, rear and side extensions, and double-storey extensions. The best option depends on the available space and your priorities. A rear and side extension maximises ground floor space.
Do all house extensions need building regulations?
Yes. Building regulations approval is required for all house extensions regardless of whether planning permission is needed. Building regulations cover structural integrity, fire safety, insulation, ventilation, drainage and electrics.
How do I find out which extension suits my property?
Book a free consultation with LCCL Construction. Our architect will assess your property, discuss your requirements and recommend the best type of extension. Call 020 8037 7332 or visit lcclconstruction.co.uk.