This is one of the most common questions homeowners want to know when considering an insulation project.
The answer? The best type for you depends on:
- How much insulation is needed?
- How accessible is the space that needs insulation?
- How much space is available for the insulation?
- What’s your budget?
Comparisons need to be based on R-value
Insulations are rated in terms of thermal resistance — R-value. The R-value tells you the resistance to heat flow.
The higher the R-value of an insulation, the greater its effectiveness. It depends on things like the type of material used, its thickness and its density. Some insulation is layered to give it a higher R-value.
It’s important to know that if insulation is compressed, it won’t give you its full rated R-value, such as when insulation batts rated for one thickness are squeezed into a thinner space.
R-value is also compromised when the insulation is exposed to air flow. Because of that, air sealing your attic is critical before adding or replacing insulation
Joists, studs and rafters in the project area will affect the R-value of the insulation too — in a ceiling for example. The insulation itself can’t prevent heat flow through those materials, so the R-value of the overall insulated area may be different from that of the insulation.
The R-value for Minnesota
It won’t surprise you that Minnesota’s R-value needs are among the highest in the nation because of our cold winters. No matter what heating system you use, they are:
- R49-R60 for attics
- R30-R60 for cathedral ceilings
- Walls have two requirements: R13-R21 for cavities; R5-R6 for insulation sheathing
- R25-R30 for floors
Don’t forget though — a properly insulated home or business is kept more comfortable all through the year. It helps keep the structure cooler in the summer as well as warmer in the winter.
Read the label
The Federal Trade Commission has clear rules about how R-values are labeled on insulation products for your home. Not only are the R-values clear, but also facts about health, safety and fire hazard issues.
You want to be sure you’re using a product that fits your situation, whether you do the job yourself or hire a contractor. Take time to read the labels before starting your project.
If you hire a professional, you can even ask them for the labels off the packages they’re using. Remember, an educated consumer is a wise consumer!