How to save thousands on your home extension

How to save thousands on your home extension

If you're planning to take advantage of the relaxed planning permission rules and build a home extension, make sure you follow these tips.

Donna Ferguson

Mortgages and Home

Donna Ferguson
Updated on 13 July 2016

An extension or addition to your home is considered to be a permitted development, not requiring an application for planning permission. But the extension is subject to limits and conditions, such as:

  • No extension should be higher than the highest part of the roof
  • The maximum height of a single-storey rear extension is four metres
  • Single-storey rear extensions must not extend beyond the rear wall of the original house by more than three metres if an attached house or by four metres if a detached house. ​

But in some cases, you will probably need planning permission if you want to build something new, build an extension, or change the use of your building. 

Here are some tips to save you a little extra cash:  

Getting planning permission

As loveMONEY understands, it shouldn't be too difficult to get planning permission for large extensions  – as long as your plans don’t have a negative impact on your neighbours or the environment. 

So yes, if you are thinking of building a large extension, being able to forgo all the bureaucratic red tape involved with getting planning permission will definitely save you stress, hassle, money and time. 

Choose a problem-fixing builder

You need a builder who can solve problems cheaply and quickly, rather than asking you what to do when. Let’s face it, you probably won’t have a clue.

Understand where your money is, and how much of it you have available, plus benefit from instant valuations of your new worth. Claim your free access to Plans today >

Hire trustworthy tradespeople who you can get on with

Dealing with recommended independent tradesmen can be a lot cheaper than dealing with a big firm, and you have a closer, more direct relationship with them which makes it easier to sort problems out.

Plus, if you get a word-of-mouth recommendation, their personal reputation (effectively, their livelihood) is at stake and they are often prepared to go the extra mile as a result.

Even if their quote isn’t the cheapest, going with the tradesperson you instinctively trust most to do a good job would be the best option – it’s likely you will save hundreds of pounds in the long run.

Be on your guard

Make sure you check all the current prices before you pay in full. You also have to be on your guard about measurements.

It might seem obvious, but a mistake here can literally cost you a fortune!

Case Study

Donna Ferguson, former loveMONEY editor lets us know how she shed thousands of pounds from her home extension costs.

Last year, I managed to get planning permission for a 30m extension to my north London flat, despite living in a conservation area and having no permitted development rights.

Still, I can’t deny it was stressful. I wrote the successful application myself, which took a lot of time, effort and research. It cost me £150 in fees, and took eight tense weeks. And that’s a relatively quick turnaround – if the application goes to the planning committee, or is turned down and you appeal, the process can easily take months or even years.

It's also important to keep the neighbours onside. Our elderly neighbour had five conifers in his back garden and when the building officer saw them, he insisted we increase the depth of our foundations dramatically. 

This would have cost us thousands of pounds extra. But when our neighbour found out about this, he very kindly offered to cut down all his trees – just to save us money!

We were flabbergasted. We had consulted him throughout the planning process and tried to be considerate throughout, but I think it was the kindness and respect our builder had shown him over the garden wall that truly won him over." Which leads her onto her next point...

Befor hiring the tradespeople for the job, I interviewed a number of builders, and when I say interviewed, I actually asked them interview-type questions like: ‘How would you approach this problem?’ or ‘How do you plan to minimise the disruption during this stage?’. I cannot tell you how good the builder I eventually chose was at solving problems. 

Not only that, you should hire a builder who is able to solve the problems that might get thrown at them. One day when I came home, the builder said: "Unfortunately, there’s this completely unforeseeable, potentially extremely expensive major complication... but don’t worry, I’ve already worked around it using this complex, little-known and very cheap method.”

To make sure I could keep an eye on my finances, I opened a bank account just for spending on the extension, and every few days, I updated our budget for various parts of the build, our savings account balances and all our building spending into a shared spreadsheet.

This allowed me to make informed decisions when faced with a potentially costly dilemma. We also took out the market-leading 0% credit card so we could keep our savings in our ISAs for as long as possible, pocketing the interest on the ISA while paying nothing on our debt.

When it comes to buying products, it's important to stay alert. One mistake I made was panicking because the floorboard or bathroom I liked was on sale for a limited time only. In fact, it turned out it was discounted pretty permanently in various sales throughout the year.

Happily, I’d only put down deposits and not paid in full, so I could choose which ‘sale’ price I paid at the point of delivery.

Have you extended the size of your home? Was it a stressful experience? What would you do differently? Let us know your thoughts in the comment box below

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More on home improvements:

How I saved £1200 on my new boiler

How to get planning permission

Best ways to pay for home improvements

Home extensions increase property value by up to 23%.

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