Cellulose Insulation: Green and Sustainable for Any Home
If you are planning to build or remodel your home, the greenest choice for insulation is wall spray or dense pack cellulose. There is no other insulation that can boast the air sealing capabilities and the 100% recycled material capabilities of this product.
How It Works
Cellulose insulation is basically ground up newspaper with some chemical additives to give it fire resistance and pest resistance. The cellulose comes in a compressed bail that is shrink wrapped in plastic. The cellulose is placed into a pneumatic hopper where it is blown into the wall cavities along with a small amount of water allowing all of the fibers to stick to each other and, of course, the wall. This application gets into all of the nooks and crannies that typical fiberglass insulation can't get into. And because it fills the entire cavity, it has extremely good air sealing abilities.
With the dense pack method, the cellulose is blown dry behind a fabric membrane that is installed over the walls. The cellulose is packed into the cavity and has the same characteristics as the wall spray cellulose application.
Doesn't It Settle?
Cellulose applied with this method cannot stay in the stud cavity unless it is applied at 3 lbs per cubic foot. Any less, it will fall out of the cavity immediately during the insulation process. After it is applied, it will not settle because of the density of the finished product.
How Long Does It Take To Dry?
The cellulose should be dry and able to be drywalled over after 12 hours. It is important that drywall be installed with in 36 hours so the bonding between the cellulose and the exterior sheeting does not where off.
Do I Need A Plastic Vapor Barrier?
The answer to this question is no... BUT if the building inspector says you have to have it, you have to have it. Vapor barriers are based on permeability rating. The general code is to a have a permeability rating of 1 plus or minus .5. Cellulose insulation has a permeability rating of 1 at 3 lbs per cubic foot at 5 a inch depth. 2x6 studs are usually 5 1/2 inches so the cellulose DOES meet the permeability rating requirement. This is not a battle worth fighting so if they say put it up, then put it up.
How Does Cellulose Compare With Fiberglass?
Cellulose outperforms fiberglass by 15-30% depending on the type of house and the lifestyle of the family occupying the space. The biggest difference that people notice is the sound attenuation of cellulose and home comfort improvement is noticeable. If you live in a warmer climate with few temperature changes, there is very little energy savings involved.
How Expensive Is Cellulose?
Cellulose insulation installed in this manner is about $1 per square foot. To insulate the average home (1500 square feet) with wall spray or dense pack cellulose insulation, blow in cellulose in the attic and spray foam in the box sills, would be around $3,000-$5,000.
Cellulose insulation has an R-value of 3.8 per inch. It is 100% recycled newspaper with Borax or sulfides added for fire resistance, pest resistance, and mold resistance. Every manufacturer has an MSDS either attached to their product or available through mail or email.
Cellulose insulation is the best choice for the truly green advocate. With energy savings and 100% recycled material with zero waste, how can you go wrong?
If you are not sure about energy updates or would like to know more about your options, it is always a good idea to hire an energy consultant. They will go through your house or a set of plans with you to determine the most efficient energy investments for your family. This service is also available on a commercial scale. Depending on your state, rebates may be available for energy efficient upgrades.