we are very excited to hear about your excellent experience with your geothermal system and are considering having it installed a new (used) house we are getting ready to buy on west side ann arbor.

I will definitely visit your blog again when we are ready to do it.

Cellulose has number of advantages as well. First, it is a recycled and recyclable material – making it an excellent life cycle choice. It is also a bit less expensive than spray foam. It is also non-toxic at every stage.

While most spray foam is not toxic in its installed state (manufacturers of icynene foams claim you can eat – but until I see them swallow a piece, I wouldn’t try this at home), it is toxic in its manufacture, and care must be taken to avoid contaminating the environment and the workers. Further, foam, like other plastics has an unknown lifespan. The good news is that it scores high on durability. The bad news is that it may be around long after your house. There are spray foams being made from bio-based sources such as soy. These can be friendlier choices, but are more costly.

Both are excellent insulators and should be seriously considered. We are using spray foam in the basement joists to help provide both thermal and air barriers. For the price, we were able to get a higher R-value with cellulose. There is no bad choice here.

As for cotton batting made from blue jeans, it is another good option with the added benefit of excellent sound insulation. Cotton batting is much more expensive and does not have any significant advantage over cellulose. Again, it’s still not a bad choice.