Insulating the home will help save money as well as energy, and what is more a lot of home insulation can be installed by the homeowner. The easiest and most prevalent of all home insulation is loft insulation, but there are other forms, such as cavity wall insulation.

-Loft Insulation

In most cases loft insulation is laid between the joists, and is made from glass mineral wool products, although new alternatives including sheep wool is also being used. The government recommends that loft floor insulation should be laid to a thickness of 270mm.

Loft floor insulation comes in a variety of widths and thicknesses, and purchasing the right type will depend on the distance between joists and also how much insulation is going to be required. Calculating how much home insulation is required though is a basic sum.

At the most basic level the calculation is based on multiplying the width of the loft by its length, which will give the loft area. Most lofts come with joists set to a depth of 100mm, and so 10 percent of the total figure is subtracted to give required loft insulation.

If the loft is going to be insulated to the recommended depth of 270mm then the loft insulation will have to be double layered. The calculation though is as simple, and comprises of a figure for insulation to joist level (width multiplied by length, with 10 percent deducted), plus a figure for the second layer (the width of the loft multiplied by its length).

To allow comprehensive insulating most DIY stores sell loft insulation of varying thicknesses. All packaging though will explain the floor coverage that each roll of insulation will fill. To find out how many rolls will be required it is then a case of dividing the loft floor area by the floor coverage of each roll.

In most cases the loft should be a cold space, but occasionally it is a living space. In this case the insulation will need to be placed in the rafters. Although blankets can be used in most cases rigid insulation boards are used. The same form of calculations though is used to work out how much insulation is needed. The height and width of one roof slope is measured and multiplied together, with 10 percent of the total volume subtracted to give a total figure for insulation required.

-Cavity Wall Insulation

Loft insulation is not the only form of home insulation available. Cavity wall insulation is another popular option to cut down energy wastage. Most new homes will already have cavity wall insulation installed but some older buildings will have a gap between the brickwork that should be filled with insulating material, although this does mean that there has to be a gap of at least 50mm between inner and outer brickwork. It is possible to calculate how much insulating material is going to be required and basically requires a measurement based on the height of the wall measured by its width, and then multiplied once again by the insulating gap. This calculation will give a volume figure. There is though little need to work out how much cavity wall insulating material is going to be needed as the work of fitting it can only be undertaken by a registered professional. The professional will work out how much material will be needed to complete the job.

Learn more about this author, Tim Harry.
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