Check attic insulation

Recently, I went up into the roof space of a modern farmhouse to have a look at the insulation.

Paul Mooney

23 October 2013

Picture one Here, as in most two storey houses, the roof insulation is on the floor of attic space, rolled out between the timber joists. There is no insulation at the rafters, under the tiled roof. This means that the heat from the central heating is kept below the attic floor and the attic is allowed to more or less follow external temperatures. This is the original roll out mineral wool type insulation that was installed 30 years ago. It was a 100mm (four-inch) deep layer which was typical

Picture two The farmer has never had a problem with pipes freezing in the attic, which is a good thing. However, it is also a sign that heat is escaping up into his attic. The insulation on the water piping is minimal and some lengths of pipe and valves, etc, are not insulated. When more insulation is added, the attic will become colder and there will be a higher risk of a burst pipe and water damage. It is important that the homeowner similarly steps up the insulation on the water pipes an

Pictures three I pulled back the insulation from the edge of the attic to show the eve ventilation opening. It runs along the edge of the roof and allows an airflow which keeps the roof timbers dry enough to prevent mould attack.

Picture four, with no camera flash, shows the size of the opening.

Picture five In a number of places in this attic, the insulation has been disturbed by tradesmen and not replaced. Here, it was lifted — years ago — to allow electric cable to be brought across to an external wall light. The bare ceiling plasterboard of the room below has been exposed, and heat escaped, in the intervening years. Again, we note how the insulation has compressed and is below the level of the joists. The bat hanging from the rafter shows that the air vents are open. Nowada

The house is two storeys high, 30 years old and has oil-burning central heating. The owners plan to have the attic re-insulated to a higher standard. This was prompted by the recent cold winters, escalating heating costs and higher awareness of the benefits of insulation.