DIY Network

Insulating Attics and Roofs (page 3 of 4)

Learn how to increase your energy savings. Use these step-by-step instructions to easily insulate your attic and roof.
Excerpted from Do It Yourself Home Improvement

More in Home Improvement

Laying Loose-Fill Insulation

Loose-fill insulation can be used as a direct alernative to blanket insulation. Which one you choose is a question of personal preference. Bear in mind that bags of loose-fill insulation are easy to handle and are simpler to transport into the attic than their blanket insulation equivalent. Also, where an attic is awkwardly shaped in its joist design and layout — it may have lots of blocking and inaccessible voids between the joists, for example — loose-fill insulation can provide a more user-friendly, easily installed alternative to common blanket insulation. Be aware that there are conventional and recycled alternatives.

Using Recycled Paper
Arguably, the greenest option in loose-fill insulation is shredded recycled paper. This is sometimes used in wall insulation, but it can also be blown into attic spaces using a purpose-made applicator. Ensure that an adequate depth has been achieved to ensure thermally efficient results.

Laying Loose-Fill Insulation

First, sweep the voids to remove any debris. To stop the loose-fill leaking out under the eaves, create a barrier where the joists meet the rafters using a small section of blanket insulation, as shown here. If your roof is covered with non-breathable felt, leave a 2-in (50-mm) gap between the roof and the blanket to allow air to circulate freely.

Carefully pour loose-fill insulation into the areas between the joists. Pour in enough to reach the top of the joists. It is best to start at the eaves on one side of the roof and work across to the other.

Cut a section of plywood to the same width as the gap between the joists. Sweep the fill away from you, using the offcut to level it off. Move excess loose-fill to areas that need to be built up.

When leveled off, you should have an even coverage across the entire attic space. The blanket insulation at the eaves will prevent "creeping."

The depth of the loose-fill will determine any further requirements regarding regulations. If you have electrical hardware, such as a recessed light from the ceiling below, build a wooden frame around it to keep the loose-fill insulation out.

Should you require a deeper layer of loose-fill, you will need a platform from which to work, so that you can safely move across the attic space, as the insulation will obscure the joists from view. A further wedge of blanket insulation may be required at the eaves.

Courtesy of © 2007 Dorling Kindersley Limited

Deep Filling

Deep filling can be achieved with loose-fill, but a more practical alternative is to use decking boards above the loose-fill, combining the two to achieve regulation depth, and creating a useable storage space in the attic. Always think about combining insulation — even if you don’t create a large storage area, the decking will provide safe access.

Excerpted from Do It Yourself Home Improvement

© Dorling Kindersley Limited 2009