Insulation’s effectiveness is measured by its R-value, which depends on the type and thickness of the insulation. When purchasing, compare the cost per square foot (installed) of your R-value choice.
Each type is made to fit in a different part of your house. Rolls or blankets are usually laid over the floor in the attic. Batts are made to fit between the studs in walls or between the joists of ceilings or floors. Loose fill insulation is blown into the attic or walls. High density damp spray is used in the attic or walls. Blown-in-blanket is a loose fill material held in place in walls or ceilings by netting.
Fiberglass is the most common type of insulation, manufactured from sand and recycled glass. Rock wool is made
from natural rocks and formed under high heat. Mineral wool is primarily made from recycled materials from steel mill wastes.Cellulose is made from recycled newsprint and cotton is often made from post-industrial recycled cloth like denim. These are treated with fire-retardant chemicals.
ISO board, XPS (blueboard), or EPS (beadboard) are usually found in rigid board form. These lightweight boards generally have an R-value of 4 to 7 per inch. They are intended for use in confined spaces such as exterior walls and cathedral ceilings.
Spray foams, used in the attic or walls, such as urethanes and polyicynene are also available with R-values from 3 to 6 per inch.
Which one is right for you? It depends on several things:
- Amount of space
- Bulk density of the materials (weight per volume) so your ceilings won’t sag
- Ease of access
- Ease of replacement the insulation in case you had a roof or wall leak
- Whether you are building a new home or improving an existing home.
To learn more about home insulation, download this pdf fact sheet from the Florida Energy Systems Consortium.