Green houses will cost extra £20 per sq ft

Building green houses as part of the move towards a zero-carbon standard will cost an extra £20 per sq ft when compared to traditional houses, according to CBRE Hamptons International. CBREHI’s When Does Green Mean Go? Report, launched at today’s Think 2007 conference in London, investigates the costs of green residential design and construction by creating and evaluating a theoretical green building designed by architect Lewellyn Davies Yeang.  The research finds that the building, which includes a combined heat and power system, a sky garden, natural ventilation and lighting and energy efficient appliances creates a green premium of £20.63 per sq ft, or around 12.5%.  Using standard building costs of £162.65 per sq ft, the cost of building a 650 sq ft flat is therefore £105,700 – an increased cost of £13,400 on the same 650 sq ft flat. CBREHI writes: “The research illustrates that there is still a question of how and when we reach a tipping point for the development of zero-carbon homes on a mass scale to become standard. “It requires the convergence of public sentiment, legislation and technology acting toward the goal of CO2 reduction.” The group adds that the research reveals that the stamp duty exemption for zero-carbon homes is “insufficient”. CBREHI writes: “The buyer of a ‘green’ 650 sq ft flat in London will see an increased cost of £13,400.  If this flat were to be valued at £200,000, the tax duty exemption would only total £2,000, and the buyer will have to absorb approximately 85% of the green premium.  “However, the same flat in a more affluent area of London, costing £400,000, will see a stamp duty exemption of £12,000, leaving the buyer to pay only 10% of the green premium.”