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House Extension Costs

How much does a house extension cost?

The price of a house extension can depend on a range of factors, but figures suggest they cost around £35,000 on average in the UK. There are many great reasons for investing in a house extension. Some people extend their homes because they have new arrivals to cater for, need to create more storage space, need an extra place to unwind, or because they want to add value to their home before they sell it. Another great reason for building an extension is to avoid moving to a new house when more space is required.

Small, medium, and large extensions costs

Small extensions normally cost between £18,000 – £40,000, whilst medium extensions normally come with price tags of £40,000 to £80,000. A large extension can cost from £80,000+. Prices work out at around £1750-£2250 per m2 depending on the spec you opt for. If your adding a second floor you will need to add another 50-70% to the cost. Elaborate and luxurious windows, doors and finishing are likely to cost you more. Foundations, supports, structure, and roofing can also be highly influential on cost. Your architect and engineers’ decisions can play a big role. Prices can also be influenced by factors like your location, the complexity of the design, and the quality of the finish.

Work involved in extensions

The work involved in building an extension can be more complex than you might think. Creating an extension requires a great deal of labour, and several professional tradespeople will play a role in your project. The work can include everything from plumbing, electrics, plastering, laying foundations, decorating, building walls, and fitting kitchens. Adding an extra storey to an existing extension can be more expensive than many people assume – it won’t cost just a fraction of the original work.

Design, build, and compliance

Before any work begins, you will need to consult an architect to draw up plans. Some people work with separate architects, whilst others receive design and build services from the same company. Not all extensions require planning permission, but it’s wise to check whether you will need it before work commences. You will also need to comply with building regulations. These regulations are designed to ensure your extension is water-efficient, energy-efficient, safe, and structurally sound.

Preparation work

The site needs to be prepared properly before work can begin. Foundations need to be dug for safety reasons. If anything needs to be moved so the foundations can be laid down, this might make the process longer, costing you more. Brick and blockwork extensions tend to cost around the same as timber frame extensions these days, so one won’t leave you more out of pocket than the other. Features including doors, skirting boards, radiators, sockets, and switches can also drive prices up, but the quality of these will determine how much you need to spend.

Finishing and completion times

Finishing prices can also vary greatly – a mid-price carpet will cost much less than marble flooring, for example. Many people build extensions to house new bathrooms and kitchens, which can also raise the price tag considerably. Completion times can also vary – whilst some extensions take two to three months, others require much more time.

Contact Steen today to find out more how about we can help you create the perfect extension for your needs.

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