Want to know how much it costs to build a house in the UK? We get the experts to explain how to work out how much you can, and should, spend on a self build. 

baufritz budget s1 build house in germany - grand designs  

Image: Not only is this S1 type kit house from Baufritz affordable to erect, it features smart energy efficiency technology that contirbutes to low running costs. 

If you're a Grand Designs fan, chances are you've day dreamed about a self build project at least one time. It can sometimes feel a bit of a mystery as to whether a self build is within your reach or, when it does come to building your own house, how much you should budget for the build. 

The truth is, self-building can be a way to really make the most of your money and create a home that you may not otherwise be able to afford. 

We asked the experts for what you need to know in setting a build budget, and how best to stick to it. 

Use average property prices as a guide 

 entarnce to modern self build home built into a clifftop featured on grand designs

Image: The owners of this clifftop house, featured on Grands Designs in 2019, bought the land for £120,000, and spent £420,000 on the build. The resulting property has a market value of £650,000. 

Data scientist Anna Powell Smith explains how to set a budget that will reflect the value of your completed project:

"Use average property prices per square metre in the area you are concerned with when deciding what budget to set for a renovation or self-build. Speak to local estate agents, builders or architects to get an idea of the local per square metre property values, or use online services that list average house prices per square metre."

Your budget should be, at maximum, equal to the average property price per square metre multiplied by the square meterage of your propsective build, minus the price of the land to avoid the build entering negative equity. 

The actual cost of the work is something that will depend on a whole range of factors. Consider using the square meterage information in tandem with a self build cost calculator to get an idea of how far your budget will go. 

We're well-versed with overspending Grand Designers by now, so building in a contingency of 10-20% is important. Having this built in from the outset will help to prevent going way  over budget.

How cost efficient is your build? 

 oak frame building in wales by welsh oak frame - grand designs

Image: The owners of this oak-framed house near Montgomery in Powys worked with Welsh Oak Frame to create a home to suit their budget, limiting more expensive building materials to the main living areas, and using budget options elsewhere. 

Make your budget go the distance by looking at contemporary forms of construction. Traditional block and brickwork can cost from £1,250 to £3,000 per square metre, while timber and light steel frames, as well as modular off-site builds, are quicker to construct and therefore reduce the overall cost. 

Mike Hardwick of NaCSBA also advises on how to plan a cost-effective build:  "The most cost effective shape of house to build is a square or rectangular footprint with a simple roof design. Complexity adds cost, as does anything bespoke, so choose readily available materials in stock sizes."

If you're considering completely renovating a home, demolishing it and rebuilding from scratch could also be on the table as a more economical opportunity as self builds are zero rated for VAT, however, you need to ensure you have planning permission to do so first. 

For more cost-saving and planning tips, read our guide to paying for a self-build project

Financing your self build 

A self-build project is a little different from buying a house. The funding doesn't all need to be in place from the outset, for example, however it does need careful planning. Consult our guide to self-build finances for more information. 


Dreaming about building your own home? Share your thoughts with us by tweeting us @granddesigns or post a comment on our Facebook page.



How to project manage your own self build

How to keep your neighbours on side during a self-build

Self build mortgages: a guide to financing your new home

Kevins Column

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