The range is anywhere between £60 - £100 per square foot, depending on the specification of the house. However, we strenuously advise people that this is a very very rough guide. Take a 2500 square feet house for example. If the specification was on the lower end of the scale (tiles, average insulation, radiators) the total would come in around £150,000.00 at £60 per sq. ft. Yet, if the spec of the house was higher (slates, underfloor heating, high insulation) the total would come in around £187,500.00 at £75 per sq. ft.