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  • Writer's pictureNíall Hedderman

How Much Does a House Extension Cost in Scotland 2024

Are costs for domestic projects returning to normal in Edinburgh?

After the inflation of the last few years, I have seen a return to competitive pricing in the house extension market over recent months. Costs aren't coming back down, but the rate at which they are increasing is not a steep as in was in 2020 - 2023 and contractors are now willing to bid for tenders, rather than direct negotiations. This is a sure sign we might be entering a more competitive environment and that homeowners may be able to plan work to their property with some confidence that costs wont jump overnight.

It can take months, even a year or more, between first approaching an Architect and eventually getting everything ready to start work on your project. Over the past few years prices rose so much during that initial phase, they sometimes put the project out of reach for my clients budget.

Why do I feel optimistic about construction costs in 2024?

First off, I completed a house extension in Corstorphine, Edinburgh and the construction costs came to £3,550 + VAT per square meter. This despite the fact the site was steeply sloping and had a split level, open-plan which required complex construction methods. This job is so recent I don't yet have proper photos of it, but I was keen to share the news.

Construction costs for a house extension Scotland 2024
House extension under construction on Corstorphine hill, Edinburgh

split level open plan living area Corstorphine, 2024
This is the split level open-plan area, a feature that usually increase costs

house extension floor plan Corstorphine Edinburgh 2024
This extension left the existing house largely intact

While this increased the construction costs, there were two features of the extension that kept costs down;

1.Changing as little inside the existing house as possible.

2.Using a flat roof, rather than a traditional pitch roof.

Had we built this extension on a flat site, the cost would be about £3,000 + VAT per square meter. That is the going rate I now quote to clients in Edinburgh at the outset of any project. It is the cost to build a basic, but competent, house extension in Scotland in 2024.

Had we integrated the extension more fully into the existing house, cutting down external walls for example, to join rooms together, the cost would have increased significantly. While flat roofs aren't to everyone's taste, and not always appropriate, the additional material, labour and time required to integral a new pitched roof with an existing one makes it more extensive than a flat roof.

A return to competitive tendering?

The second project that was interesting, involved knocking a load bearing wall and joining two rooms together. This will create a very nice living space, right next to the garden but the big news is that I was able to persuade two building firms to participate in a competitive tender process. This is the first such tender I have run since 2019. I have run another one since then and have others in the pipeline. It is clear that builders at this end of the market are not as busy as they were last year.

knocking a load bearing wall
The plan is to knock the wall on the right

Work will start on this project next week and should be complete in July. While the project involves a lot of changes to the interior space and to the exterior, including creating a large opening in the eternal wall to fit a patio door, the cost to take down the load bearing wall has come in at just under £10k + VAT. Added to that is about £11k + VAT of remedial works to the floor, ceiling and adjacent walls, including laying new flooring etc. So the overall cost to take down a 4m long load bearing wall in a 19th century home in Edinburgh comes to £21k + VAT in 2024.

floor plan of an internal alteration project in Edinburgh 2024
The thin dashed red line shows where the wall will be taken down between the rooms

I hope this gives you some idea of current costs for house extensions and internal alterations in Scotland in 2024, especially in the Edinburgh area. It should also give some hope to anyone planning a project that costs may have stabilised and contractors are keen to bid.

It is possible to design alterations and extension to your home with the specific goal of keeping costs under control but it requires both compromise and flexibility. If you want to discuss a project with me, get in touch.

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