Attic insulation can drastically reduce heating and air conditioning bills. There are many insulation options available as this site points out, which include sheets of insulation and loose fill insulation that can be cellulose or fiberglass. The age of the attic is not as important as the type of construction of the attic. The type of construction will determine the choice of the most appropriate insulation type. The replacement of the existing insulation may be necessary due to the circulation of air or moisture problems.
There are a number of indications that the attic insulation may need to be replaced or increased. If an owner has seen an increase in their heating bills, it is possible that the house is suffering from air leaks that are causing drafts in the winter. These drafts can be discovered when a specific room, an area or a floor in the home is colder or hotter than elsewhere. You can also inspect the condition of your insulation. When there are air currents and cold winter air mixed with the hot air from the house, condensation can occur causing mildew. Condensation and mildew can also cause damage to the ceiling.
If you discover any filtration of air, moisture, condensation or mildew problem in an attic, you will then need to perform some repairs and prepare for the installation before placing additional insulation or installing new insulation. All the holes in the attic must be repaired to prevent the flow of air. Sealing the holes automatically reduces heating and cooling costs, and most of the moisture and condensation problems can be resolved. Any insulation damage with mildew must be removed and the mildew should be treated to prevent growth in the future.
The sheets and the insulating rolls are types of insulation that are relatively easy to install. This material is available in rolls and sheets, as the name suggests. They can be purchased at various widths so that it corresponds with the structure of the building and can be simply installed between joists. This material can be applied in two or more layers arranged in different directions to help seal the cracks. If the beams in the building are irregular, the material can be trimmed with scissors or any manual cutting tool.
A second type of insulation is loose insulating filling. This insulation is mainly used in construction, where the attic space is uneven and the installer does not want to cut several pieces. Due to its loose composition, this material helps to fill irregular spaces and can be quickly installed with a blowing machine or with manual spill procedure.
A great resource for more information about insulation can be found at the Energy Saver.