House Extension Costs You Can Avoid Spending in London

Living Room house extension idea

Have you always dreamed of a house extension but the cost is too daunting? Maybe you’ve done some research on a spacious new kitchen or additional bathroom, but you’ve never been able to figure out exactly how much an extension would cost. 

We’ve put together this guide to help you navigate through the financial commitment of a house extension in London so you can finally figure out if it’s the right move for you. 

How Much Does It Cost To Build An Extension On A House?

The cost of your project will depend on whether you’re opting for a single or two-storey extension. As well as whether or not you need any plumbing work added. 

Costs for a dining room house extension

Single-storey extension

For a high-quality single-storey extension in London, it will cost around £1300 to £2,000 per m2. You can bring this price down by using basic materials, but you won’t get the same high-end finish. 

For example, if you’re looking to add a rear house extension that’s 5m x 5m, that’s going to cost you anywhere from £32,000 to £50,000. 

You’ll also need to budget for architect fees, planning permission, a structural engineer, a contractor, and a build team. All of which can cost anywhere from £8,000 to £20,000, depending on the complexity of the extension. 

For example, a terraced house extension is going to be more difficult if the rear of the property is difficult to reach with materials. 

Two storey extension

If you’re going for a two-storey extension, this will be around 50% more than the cost of a single-storey. Plus an additional 10% for fees and labour. 

Taking the example above, you’d be looking at an additional £16,000 to £25,000 for the build. Plus an additional £800 to £2,000 for fees and labour. 

Plumbing Work

Extensions become pricier if you’re looking for a kitchen or bathroom. This is because additional planning permission is required for plumbing work and then a professional plumber is needed to run all new pipework. 

A bathroom will cost an additional £5,000+ on top of the build. Whereas a kitchen extension will be anywhere from £10,000 upwards, depending on the level of finishes you choose.

How To Finance A House Extension

A terraced house extension

If you love the idea of an extension but you’re not sure how you could afford it, here are some options:

  • A home improvement loan: A home improvement loan is usually cheaper than a personal loan and is added to your mortgage. This loan is secured against your home so it’s important to keep up the repayments to avoid your home being repossessed. 
  • Remortgage: Mortgage rates are usually significantly lower than loans and usually allow overpayments without additional fees, meaning you can pay the additional money off sooner. 
  • Personal loan: If you don’t like the idea of securing a loan against your home, you could apply for a personal loan. These often have much higher fees than home improvement loans though, so make sure you’re happy with the fees and repayments. 

How Much Does An Extension Add To The Value Of A House

When valuing a home, estate agents take into account the number of bedrooms, bathrooms, and the overall square footage. 

If your extension adds an additional bedroom or bathroom to your home, you can easily add around £20,000+ to your home depending on the quality of the extension and the location of your home. 

Dining room house extension

That’s not to say a garden room extension won’t add value – it is still adding square footage to the property. But it won’t be as valuable as a kitchen or bedroom. 

A kitchen extension is another type that can add significant value to your home. However, it’s important not to overspend in order to maximise the return. 

5 Tips on Cutting Your House Extension Costs

You should never compromise on the quality of materials used during an extension build, and you definitely don’t want to rush through the job to cut costs. Instead, here are some house extension ideas that will help you cut costs effectively. 

1. Take Advantage of Connections

Do you know anyone in the trade business? Tradespeople and contractors often have access to discounts that the general public don’t. Reach out to any friends or contacts in the industry and see if they have any trade accounts you could take advantage of. 

2. Avoid Bespoke or Custom Made

Features such as custom-built roof lights or a bespoke kitchen can significantly increase the extension cost. Instead of opting for bespoke features, try to buy off the shelf first. 

Many elements such as roof lights that come ready built look fantastic and save a chunk of the budget compared to architectural glazing. 

Living Room house extension tips

3. Avoid Relocating Fixtures and Pipework

If you can leave the boiler where it is, we recommend you do. The same goes for toilets or other plumbing fixtures. 

Having to replumb pipes to new locations is costly, especially if you plan on relocating to an awkward location. It might also involve planning permission which is an additional cost. 

4. Negotiate

When undergoing an extension, you’ll be working with many service providers and purchasing dozens of different products. Although it can take more time, negotiation will get you the best price for everything, helping keep the budget in check. 

When finding the right team for different services, make sure you get several quotes for the same job so you get the best price. 

Negotiating well for services and products can easily save you up around 20% on the total cost – which is a pretty sum when taken off the total of the project. 

5. Choose the Right Build Team

You’ve probably heard horror stories from friends and family of builders who started a project and then disappeared with the purse.

This is why it’s incredibly important to find the right build team that you can count on when planning an extension. 

At Master Build Team, we’re upfront about the house extension cost, timeline, and keep our clients in the loop throughout the whole project. 

Having a specialist build team you can rely on is one of the easiest ways to keep your budget in check and take advantage of professional connections. 

Thinking About Building an Extension on Your Home?

All of our clients have the same issue when they come to us: they love their family home but just wish they had more space. 

That’s the beauty of an extension – you get the additional space that would make family life so much easier without having to say goodbye to your beloved family home. 

Are you planning to extend your home? This is why we’re here. Contact us today and let us know how we can help you.

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