batts vs blown-in insulation
How Do They Work?
Batts and cellulose work as insulation by acting like a barrier between your home and the outside environment. This can work in two ways: to retain the heat within your home, or to keep the heat out of your home to keep it cool. Insulation, such as batts and cellulose, can keep the inside temperature of your house up to 46ºF to 53ºF cooler than a house that is not insulated. Having a properly insulated home can both reduce energy costs by up to 40% and help to eliminate greenhouse gas emissions.
Thanks to insulation, your home's temperature can be kept cool or warm and much more comfortable and efficient. Of course the way batt and blown insulation works is through the absorption of heat, but there are three different types of heat you must take into consideration when talking about insulation:
- Conduction: This occurs when there is contact between two materials with differing temperatures. For example, if you touch a hot pan with you hand, the heat is transferred and you will most likely get burned. Batts and cellulose are made with this in mind and the air pockets within the material acts as a poor conductor, which in turn blocks heat transfer.
- Radiation: As we all know, the sun gives off heat and can warm objects such as our roofing. This in turn can heat up your attic and transfer to your home. Batts and blown-in insulation help to absorb the heat that is transferred by the sun.
- Convection: Air acts different whether it is cold or warm. As you should know, warm air tends to rise while cold air falls below. This is considered convective air flow and both types of insulation combat this type of heat transfer by trapping air in the small pockets within the material.
Insulation longevity is important to ensure extended energy savings. The great thing about fiberglass batt insulation is that it wont settle over time and deteriorates at a slow rate. Cellulose ont he other hand deteriorates a bit quicker and can also settle. Batting is similar to cellulose when it comes to fire retardency, but has a slight advantage because it's made from non-flammable resources: sand and recycled glass.
Both types of insulation don't require any additional chemical treatments, which also means they're safe to use. When talking about insulation, it's also important to understand how moisture can impact performance. If insulation gets wet, it will lose it's effective R-value and become useless. The good thing about fiberglass batt insulation is that it does not absorb moisture. The insulation might get wet, but will quickly dry and retain its R-value. Cellulose on the other hand is much more susceptible to moisture.
Both of the insulation types have a similar R-value, but fiberglass battings wins out by a small margin. When talking about environmental impact, both types of insulation are also very close, with the slight edge going to cellulose. Now many people may argue this, stating that cellulose requires more raw material (tress) to be used, especially considering it takes three times as much cellulose to insulate the same amount as fiberglass batting. Another arguement would be that batting comes from mostly sand - which is considered to be a "rapidly renewable resource" (U.S. Environmental Protection Act).