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What will it cost? A straight answer, in ranges.
Choose your project, its size and the level of finish. The range updates as you go and includes VAT. It's built from example rates for this demonstration; a real Garside quote is line-by-line and fixed after a survey.
Why ranges, not a number
Three things move the price more than size.
We'd rather you hear this from us before the survey than after it.
What's under the ground
Clay, tree roots and old drains change foundation depth. On London clay near big trees, foundations can double in cost.
Glass
Large sliders, structural glass and corner glazing are the biggest single swing in an extension budget.
Your neighbours
Party wall awards, access and shared walls add time and cost. We price them in rather than leaving them as a surprise.