Building a new house

Floor area sets the shape of the budget, but four other things decide whether the final figure lands anywhere near the first one. The site comes first. A level field with road frontage, firm ground and services at the boundary is the cheap start. A slope means retaining walls and fill. Soft or wet ground means a deeper dig or an engineered foundation. A long entrance means a long driveway, a long ESB run and a long water pipe, all paid for by the metre. If there is no mains water you are drilling a well, and if there is no public sewer you are putting in a wastewater treatment system sized by a site assessment. None of that shows in the finished house and all of it is real money, so it belongs in the budget on day one rather than in a panic in month three. Second, the envelope. New houses are built to the current energy standard, which in practice means thick insulation, an airtightness layer that has to be continuous, mechanical ventilation and a heat pump instead of a boiler. That standard is not optional and it is not where you save. Third, glazing and roof shape. A simple rectangle with a cut roof and standard windows is the efficient version. Every corner, dormer, valley, rooflight and sliding door adds labour on top of the unit price. Fourth, the finish level. Two identical shells can differ by the price of a small car once you choose the kitchen, the stairs, the floors, the sanitary ware and the ironmongery. Over all of it sit fees and certification. Your design team signs the house off under the building control regulations, so the architect or engineer, the assigned certifier and the BER assessor are a fixed part of the cost, not an extra. Construction work is charged at the reduced rate of VAT, currently 13.5 per cent, and our quotes state whether the figure includes it.

Turnkey, or to a stage?

Plenty of people building their own house want us to bring it to wind and watertight, then finish the inside themselves over a year or two. That works, and we price it that way when you ask. Be honest with yourself about which trades you can really source, because a shell standing open through an Irish winter costs money in dampness and in interest. We will tell you which stages are safe to stop at and which ones you should push straight through.