Timber frame construction

Start with what actually changes. The foundation, the drains, the slab, the roof covering, the windows, the plumbing, the kitchen and the driveway are the same either way. What changes is the wall that holds the house up and the order in which the weeks are spent. A frame is cut in a factory from the engineer’s drawings, delivered on a lorry and stood on your slab in under a week. The roof goes on top of it immediately, so the house is closed in while a block build would still be at first floor level. That matters most for two reasons. It takes the Irish weather out of a big chunk of the programme, and it brings your finishing trades forward, which is real money if you are paying rent or interest while you build. It also means the building dries out faster, because there is no wet plaster on the outer walls and no mortar holding water. The trade off is that a frame gives you far less room to change your mind. Every window opening, every internal wall that carries load, every stair opening and every steel is fixed when the frame is ordered. Moving a window after delivery is a carpentry job on a structural panel, not a case of leaving out three blocks. Second trade off, and people rarely hear this one until they are living in the house: a frame wall is light, so you cannot hang a heavy mirror or a wall mounted television wherever you fancy. Noggins go in where you tell us before the boards are fitted, so we ask for the television, the shelves and the bathroom fittings on a plan at first fix. On heat and comfort there is no simple winner. A frame heats up quickly and is well suited to a heat pump running steadily. A heavy block house holds heat longer. Both meet the current energy standard because both are designed to.

What is actually in the wall

From the outside in: a brick, block or rendered outer skin, a ventilated cavity, a breather membrane, the studs with insulation between them, an airtightness membrane taped at every joint, then a service cavity for cables and pipes, then the plasterboard. That service cavity is the detail worth paying for. It means no electrician ever cuts through the airtightness layer, which is where badly built frame houses leak heat and let in draughts.