Planning an extension? Don't forget the costs before the building even starts
Updated: Oct 30
When people start budgeting for an extension, understandably most of the attention goes straight to the build.
“How much will my builder charge?” It's an important number, of course. But there are quite a few steps before anyone arrives with a digger, and these have costs attached to them too! So I thought it might be useful to talk about the pre-build budget.
Before work can begin, you may need a measured survey of your existing home, architectural design and drawings, a planning application, structural calculations and Building Regulations information. Depending on the project, there may also be things such as drainage surveys, arboricultural reports or Party Wall matters to consider. Not every project needs every one of these, but it’s worth knowing about them from the beginning rather than discovering them halfway through.
Planning application fees themselves have also increased from 1st April this year, which is another reminder that the budget for an extension isn't simply the cost of bricks, windows and a kitchen. I know that list can sound slightly daunting, particularly when all you really want to do is create a lovely new space for your family!
But actually, I think knowing about these things early makes the whole process less stressful, not more.
One of the biggest parts of my job happens long before building starts. It’s helping clients understand the route ahead: what we need, when we need it, who else needs to be involved and roughly when the various costs are likely to appear. That way, instead of feeling as though you're constantly being presented with another unexpected bill, you can plan for the project as a whole. And I’d always recommend keeping a contingency too. Houses have a habit of revealing the odd surprise once work begins, particularly older ones!
The goal isn't to frighten yourself with a huge spreadsheet of every possible expense, it’s simply to go into the project with your eyes open because the more clarity you have at the beginning, the easier it is to make good decisions later. And when you're making quite a lot of decisions (trust me, you will be!), that little bit of breathing room is invaluable.
Planning your own renovation?
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