After building the previous house in 2001, I ended up with a formaldehyde allergy. So, I was trying to be cautious about product selection this time.
We have a great building envelope design that relies on rigid foam as a thermal break and the air barrier. But.....now I'm reading about the dangers of flame retardant (HBCG) in all of those products. It becomes air-borne in dust and has long-term health consequences. The chemical is now banned in Europe and being phased out in the US, but building products have an exemption for a while. It's also found in a number of other products in the home.
Additionally, foam insulation can have global warming consequences - which we knew, so we were limiting our use and making choices based on product impact.
Turns out Johns Manville has a polyiso board Energy 3.E that eliminates the chemical and has low GWP -- but you can only get it special order and have to buy a truck load at a time.
So....EPS foam under the slab is acceptable to me because it will be encapsulated and mineral wool hasn't been used enough in that application. The cost to install dense pack cellulose in our area seemed pretty high, so we were looking at mineral wool.
Making "good" choices is hard....and as you learn more it gets harder.
We have a great building envelope design that relies on rigid foam as a thermal break and the air barrier. But.....now I'm reading about the dangers of flame retardant (HBCG) in all of those products. It becomes air-borne in dust and has long-term health consequences. The chemical is now banned in Europe and being phased out in the US, but building products have an exemption for a while. It's also found in a number of other products in the home.
Additionally, foam insulation can have global warming consequences - which we knew, so we were limiting our use and making choices based on product impact.
Turns out Johns Manville has a polyiso board Energy 3.E that eliminates the chemical and has low GWP -- but you can only get it special order and have to buy a truck load at a time.
So....EPS foam under the slab is acceptable to me because it will be encapsulated and mineral wool hasn't been used enough in that application. The cost to install dense pack cellulose in our area seemed pretty high, so we were looking at mineral wool.
Making "good" choices is hard....and as you learn more it gets harder.