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A guide to extending your home

Do you feel that your house would be perfect for you if you just had that extra bit of space? Perhaps another bedroom or a playroom for the kids? But you may have just spent the last year or so putting your own stamp on the house and making it finally look like yours, so the thought of moving house doesn’t quite feel right.

Well, with the cost of moving house increasing all the time, many people are considering staying put and extending their homes to get that extra living space they need, plus it’ll hopefully add value to your house too!

With so many options available - front house extension, rear house extension, loft conversion, flat roof, pitched roof, single storey extension, two-storey extension... the list goes on, it can be confusing knowing where to start and who to go to to get your information.

In this guide, we’re going to give you the low-down on home extensions, including planning permission and building regulations, costings, and tips on choosing your architect and builder.

Planning permission for extensions

The general rule of thumb is the larger and more significant improvements are likely to need planning permission from your local government, and the smaller, less obtrusive improvements are likely to not need permission - this is known as permitted development.

Whether you need planning permission or not depends on a number of factors. As long as the plans for your extension adhere to the following rules, you won’t have to get planning permission for the work:

1. The extension isn’t higher than the highest part of the roof of the house.
2. If a single-storey rear extension, it should not extend more than three metres beyond the original wall of the house, if a semi or terraced house, or four metres if a detached house.
3. A two-storey or more extension should not extend more than three metres beyond the original wall of the house.
4. The maximum height of a single-storey rear extension is four metres.
5. A single-storey side extension should have a maximum height of four metres, and the width should be no more than half that of the original house.
6. A two-storey extension has to be at least seven metres to the rear boundary.
7. Materials used need to be similar or match the appearance of the house.
8. No balconies or raised platforms

Please note - if you’re planning to extend a new build house then you might need permission from the developer who may charge you a fee.

Building regulations for extensions

Building regulations is a requirement for any type of extension as it confirms that the work carried out is structurally sound, such as drainage, electrics, external and internal walls, roofs etc. But first things first, you’ll need to get the architect to draw up the plans that you can then submit.

To read the full list of planning permission and building regulations, visit the government website or contact your local council for more information.

How much is a house extension?

Obviously the cost of an extension will vary depending on what you want and also where you live.There are lots of different suggestions out there on how much an extension costs. A lot of these figures are worked out per square meter, for instance, a single-storey extension would typically cost around £1,000 per square metre. So if you were having a 3x5m extension, it might cost around £15,000 for a single-storey, or up to £50,000 for a two-storey.

Once you know what sort of extension you’d like, the best thing to do is get a few builders to come round and give you an accurate quote for the cost.

Choosing your architect and builder

When it comes to choosing your architect and builder, you want to know that you’re using someone who is trustworthy and experienced, afterall, you’re about to spend a large amount of money on what might be your forever home. For that reason, most people find them via recommendations, as people trust friends and family more than anything else.

When finding an architect, you need to look out for signs that they’re listening to your exact needs, as they’re going to be creating something that’s tailored to you so listening to your requirements is key - just make sure you give them a good brief of what you would like. An architects knowledge and expertise is also crucial as they can make good recommendations and help work around any obstacles that might stand in the way.

Many architects work with a network of builders so are likely to be able to recommend a few if you don’t already have a builder contact. Similar to architects, you want a builder who is experienced, so it’s worth asking to look at their portfolio to get an idea of previous jobs they have worked on and what their capabilities are. Also, prepare a brief for them so they know as much about the job as possible - obviously you can share the architects plans if you already have them. Don’t be nervous about getting a few different builders round to give you quotes, and be sure to check exactly what their quote includes.

When it’s time to make your final decision it’s often a case of weighing up the quote with the time scales. For instance, one builder might be cheaper than another but has a 4 month wait time, whereas another builder who is slightly more expensive might be able to start in the next month, so it all depends what’s most important to you.

Funding your home extension

There are several options for how you can fund the project. You can take out a loan for the house extension from your existing mortgage lender, or you could consider remortgaging.

If your current mortgage deal is coming to an end soon anyway, then it’s the perfect time to remortgage and use some of the equity you’ve built up to pay for, or put towards, the extension. By doing this, you can also take advantage of current low interest rates. Because of cheap interest rates, even if you already have the savings to fund the extension, you might decide to keep hold of this and use it for other things, such as a car or a holiday, as borrowing is so cheap at the moment.

Seeing as mortgage rates are low right now, it’s worth shopping around to see if you could be a on a cheaper rate perhaps by switching to a different lender. At Mortgage Advice Bureau, we work with over 90 different lenders and have access to over 12,000 different mortgage products, so we can help find the right one for your circumstances.

See if you could save yourself some money by getting in touch with us today.

Because we play by the book we want to tell you that…

Your home may be repossessed if you do not keep up repayments on your mortgage.
There may be a fee for mortgage advice. The actual amount you pay will depend upon your circumstances.
The fee is up to 1% but a typical fee is 0.3% of the amount borrowed.

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