High Quality House Extensions In London

Looking for a new loft, extending your kitchen, building an external building, side return or opening rooms? Red Box has the necessary expertise to undertake a house extension in London.

We work with architects, planners and structural engineers, as and when necessary. We ensure project integrity and best design alongside our expert builders.

We specialise in bespoke home repairs, extensions and building projects across South West London and surrounding areas. A home extension can help you make more of the space without moving home. If you’re looking to sell your home later on down the line, an extension can also increase its value.

How Does Our Home Extension Service Work?

For many years, Red Box has been one of the best home extension companies that Londoners have turned to for help. We undertake a wide range of extension jobs in London and beyond. We have plenty of knowledge, expertise and experience to share. Whatever plans you have for building an extension, we approach tasks in a series of clear steps.

Refurbished Kitchen Showing Sinks and Taps

Initial Quotation

Whatever your house extension idea, we provide a full, transparent no-obligation quote for every project. This covers ideas, needs, budget & timeframe. We price every house extension carefully. It is easy to arrange a visit from one of our team.

Project Planning

If you give us the green light we will be with you every step of the way as the project is planned. We can guide you through any extension building regulations and house extension planning permission required. Our schedule will minimise disruption during the works. You’ll always know everything is happening when it’s supposed to.

Home Survey

If we haven’t surveyed your home as part of the quotation, we will take accurate measurements. We can ensure everything fits to a tee before starting work.

Project Delivery

Our teams of builders and tradespeople are highly skilled and experienced. This means we’re confident everything will run smoothly during construction. We’ll leave your property in tip-top condition. We can finish off the painting and decorating of your house extension should you wish. All you have to do is enjoy your new space.

About Home Extensions

Do you need more space for your home, but don’t want to move? Then a property extension may be the answer! Planning a kitchen extension, side extension, loft conversion or other structural change in your home can feel daunting. Relax, Red Box helps you at every stage from planning and design to building and even decorating.

We take the stress out of the process – allowing you to enjoy your newly improved home. We have built rear house extensions, and front, side and wraparound extensions across London. The options are endless.

We can help plan the best use of the space, suggest materials and talk you through design options. Craving extra light? We can help you with a conservatory or build in large windows, for example.

Kitchen Extension London

Based in Fulham, we work with clients throughout South West London and Surrey including Fulham, Chelsea, Wandsworth, Clapham, Balham, Kingston, Wimbledon and elsewhere.

Contact us for details or visit our interactive project map to see where we’ve completed home extensions.

The Types Of House Extensions We Can Deliver

There are plenty of options when it comes to home extension ideas including side return extensions, wrap-around extensions and rear and side extensions. It can feel a bit confusing but don’t worry. Read on for explanations of each.

house extensions ideas

Rear Kitchen Extension

A rear building extension is a simple add on to the end of the property. It can usually give approximately another 5 metres to the home. Many opt for large roof windows to let in natural light. Rear extensions mostly have flat roofs, centre pitched roofs or monopitch roofs.

Side Return Extension

This is the most common type of extension in South West London. It involves extending the building typically by 1.25m to the side. This new section will finish flush to the back of the main part of the property. The roof will then be typically flat or pitched.

Wrap Around Kitchen Extension

A wrap around is a combination of both of the above options, it extends to the side and back providing a new kitchen or living space. Our team can talk you through the options and recommend the best approach.

Kitchen Extensions in London

Kitchen extensions in London are relatively cost-effective and versatile. Increasing London house prices mean moving home is often not an option. Simpler London Planning Regulations have encouraged more homeowners to extend their properties. Turning a small kitchen into a large modern space is attractive.

Our expert home renovation teams can help you find out what planning restrictions might apply in your area. We can help you work around them to get you that extra space you need. You can then trust us to get on with the job – including adding the relevant electricity and plumbing too.

Red Box has completed high-quality kitchen extensions for homeowners throughout South West London and beyond. These including rear kitchen extensions and side return extensions. Prices vary from project to project, but our team can provide a free site visit and quotation. This will help plan and provide a quotation for your specific needs.

Union Wharf new kitchen

Whether you have already started work designing & planning your kitchen or starting from the beginning, we can help. We work with a network of architects and interior designers too. They can help complete projects to the highest standard and get our clients their dream kitchen!

Refurbished Kitchen

Single-Storey Extension in London

Planning a single-storey extension for your home? Whether it be for a kitchen, dining room, living room or playroom, it’s a great way to improve your home. More space is likely to increase your property value too. A single-storey rear extension is the most popular type. As outlined above, they are mostly used for kitchen extensions. They provide a wealth of options and can feel light and airy thanks to roof lights and popular bi-fold doors.

The cost of your single-storey extension will depend on the size and scale of your project. Prices are, however, usually calculated by square metre. Average sized single-storey extensions of 4mx5m might cost around £30,000. The real figure will depend on plumbing, power, painting and decorating. Professional fees and planning costs will need adding too. The first step is to contact us for an accurate quote. We will liaise with you throughout the entire project. All you need to do is imagine what you’ll you’re extra space for.

Double Storey Extension in London

If a single-storey extension is not enough space, why not consider something bigger. A double story extension will naturally be a bigger project. The result will, of course, lead to dramatically more space. For terraced houses, most two-storey extensions are often created at the rear of the property. They are often used to extend the kitchen and add another bedroom. Extending a semi-detached house often means a two-storey side return option. As with a single-storey extension, you need to consider your needs carefully before you start.

If the ground floor will be for the kitchen extension, do you need space for a utility room or storage? Will the second storey be used for an extra bathroom, bedroom or office? The function of each room will determine the end price. You’ll need to consider power, plumbing and so on.

Frequently Asked Questions

Average extension project costs vary from £1,350-£2,250/m² of new internal space. The actual answer is, however, dependent on a wide range of factors including size, style and materials. House extensions in London can come at a premium too. You may also have to consider architect fees. They typically are 5-7% of construction costs. They include structural engineering fees, survey costs, planning costs and other paperwork too. The best thing to do is ask us for a no-obligation transparent quote.

You may need building extension planning permission, depending on the size, scale and ambition of the project. At present, you can build a single-storey extension of up to six metres to your home. The distance is eight metres if your home is detached.

Yes. We’re here to help you with your home extension plans every step of the way with expert advice and services. We can work on your behalf during the planning phases of your project should you wish.

For a relatively straight-forward extension, build-time could be three to four months. Of course, all projects are different. We can advise customers as to a likely schedule when we provide a quote.

On average, extensions are reported to add between 5% and 8% to a property value. This, of course, is not necessarily a useful guide to your specific project. If you are thinking of adding an extension as an investment, it might be worth speaking to a local estate agent. They will be able to tell you about property values before starting. You’ll know what to expect.

We certainly will. We are experts at home extensions and can manage the project from beginning to end for you. We will minimise disruption and deliver a finished product of the highest quality. 

We generally use our own staff. Your project will be managed by a member of our team. We do occasionally use contractors for specialist tasks such as plumbing and electrical work depending on your requirement.

Our home extension teams work all over London and the South East. We like to keep busy, but we are typically free for projects with a few weeks’ notice. It is easy to contact us to check.

Why Choose Red Box

We specialise in home improvements, extensions, kitchen fitting and bathrooms as well as the associated services of plumbing, electrical and full decoration work.

Our team work closely with architects and designers, either engaged by us or which you may have already engaged. We are happy to follow your design or work with you on a design to fit your budget and taste.

We’d love to hear from you!

For any questions please fill out the quick form on the right to drop us an email and we will be in touch.

Other services we provide

Kitchen Fittes London

Kitchen Fitters London

Bathroom Renovations

Bathroom Renovations

Painters and Decorators

Painters and Decorators

Loft Conversions

Loft Conversions London

Home Maintenance Service

Home Maintenance Service