Insulation
Photo: rockwool being installed
The purpose.
Why do we insulate? Think of insulation as something that slows the transfer heat. The more insulation you have the harder is for the heat to move through that assembly. Slowing heat transfer down is one of the main things that allows us to keep the inside of you home cool in the summer (keeps heat out) and warm in the winter (keeps the heat inside). The slower the heat transfer is the less our heating and cooling must work to maintain temperature.
R Value
The "R-value" is a measure used to assess the effectiveness of insulation in building materials. It indicates how well a material resists the flow of heat. The higher the R-value, the better the insulation’s effectiveness at reducing heat transfer.
Types.
If you are considering insulating a wall or ceiling/roof there are three basic types of insulation that we would consider in our market. There are of course more, but we are limiting this discussion to the three that are readily available in our market, are easy to work with, and are cost effective for their particular benefits.
Fiberglass: available in batts(for walls) and blow in (for ceilings). This is the cheapest insulation option, but also has the Lowest R Value per inch of thickness (ie. a 2x6 wall will be R-19).
Rockwool. This is a mineral fiber insulation made from minerals and recycled slag from the steel industry. Its flame retardant, has a higher R Value per inch than fiberglass. A little more expensive than fiberglass but about 20% more efficient. We love this for wall insulation, but in certain situations can be used as exterior insulation but this is less common.
Foam. Foam is a great way to insulate a roof line and encapsulate your attic. Make sure you understand open v closed cell, and proper conditioning techniques if considering this route. We feel foam in the walls is not worth it, as we achieve our tight air sealing techniques utilizing other techniques.