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Q&As
What will it cost to build a basement?
Because our plot is quite small, we are having difficulty finding a design with the space we need for our family. We are considering incorporating a basement into the plan, but are concerned about the extra expense involved. How much would it cost?
One Answer
Provided that there are no problems with ground conditions, it should cost about an extra £400 per m² of the basement floor area. This would include the excavation, walls, waterproofing, electrics, heating and a staircase. This figure only applies to basements being constructed before the house is built – installing a basement into an existing dwelling is a far more expensive project.