Insulating Your Loft

25 per cent of all the heat lost from the average home is lost through the roof. Good insulation will make your home feel warmer, whilst reducing your energy bills. This is good for your pocket and the environment. The simplest way to reduce heat loss is to lay insulation between the joists.

Safety

When working in the roof space of your house, it is good practice to wear protective clothing. Some of the materials you will need to handle could be an irritant to both skin and eyes; it is therefore a good idea to wear overalls and gloves, goggles and a dust mask. It is also a good idea to wear protective headgear due to the low beams. You also need to remember that unless your attic has been boarded out properly, you can only stand on the joists. Standing between them will almost certainly result in a hole in the ceiling below, and also possibly a broken leg/arm/neck. Use strong boards or planks in the area you are working.

Insulation Materials

There are several different kinds of material you can use to insulate your roof. In almost all cases, the recommended depth is 200mm (8in). However, this might not be possible in some cases if, for example, the joists are not deep enough.

Loose-fill Insulation

Loose-fill insulation such as Vermiculite comes in bags and is very simple to use. You simply pour the insulation granules between the joists and level it off by scraping a flat length of wood along the top of the joists. A dust mask and goggles are essential if using this material, as it is often pretty unpleasant to work with.

Blanket Insulation

This is probably the insulation of choice in a large percentage of homes. Blanket Insulation is rolls of glass fibre, mineral fibre or rock fibre, which is laid between the joists. Check the spacing of your joists before buying the blanket insulation as it comes in a variety of widths. Rolls are usually 6 to 8 meters in length. If a length is not long enough to fill a complete gap, make sure you butt the two pieces together well. Also be sure to wear gloves and a mask before handling blanket insulation material, as it can be an irritant.

Slab Insulation

This is basically the same as blanket insulation, but comes in large slabs rather than rolls and is often more dense. As with blanket, slab insulation comes in a variety of widths to fit different joists gaps. You can also buy extra high-density slabs, which can help with sound insulation. Simply lay the slabs into the gap between joists and cut to fit as necessary. As with other insulation types, wear gloves and mask to avoid irritation.

Extra Insulation

As well as placing insulation in the gaps between the rafters, you can also attach insulation directly to the roof rafters. However, you need to leave at least 50mm gap between the underside of the tiles and the insulation material to allow air to circulate. The easiest method of adding insulation to the rafters is using foil-backed insulation blanket. This is bought in rolls and simply stapled to the underside of the rafters. Overlap each strip as you work your way up the rafters. Other methods include using semi-rigid slabs of glass fibre or mineral fibre and thermal insulation plasterboard. Plasterboard has the added bonus of leaving you with a finished surface for decorating (if, for example, you are converting the loft).

Lagging Pipes

Lagging exposed pipes in the loft can save a lot heat-loss and reduce the risk of pipes freezing and bursting in cold weather. You can buy foam pipe lagging, in various thicknesses, reasonably cheaply. This almost always comes with a cut all the way along one side, allowing you to simply slip it over the pipe. Butt pieces together and join with strong adhesive tape.

Hot Water Tank

This is not always found in the loft, but the same advice applies. Hot water tanks need an insulating "jacket" made of mineral fibre wrapped in a plastic coat. This is fitted around the hot water tank and held in place with straps.

Green Roof

If you need a complete insulating solution, a green roof might be the best one. It consists of 6 to 8 different layers of roofing materials to provide perfect insulation and ultimate environmental behaviour. It will not only stop water and humidity entering the concrete, but it is an extraordinary UV rays barrier and also provides excellent heat and noise insulation. Environment Canada found that a green roof can save up to 25% of summer cooling energy needs.
More information about green roofs at www.Green-The-World.net

Insulation Tips

- Leave the space under the cold-water tank free from insulation material. Warm air rising through the ceiling can help avoid the water freezing in very cold weather.

- Remember to insulate the back of the access hatch. This can be fixed with tape or glue around the edges.