Quote:
Originally Posted by xmostynx  does it really matter what kind of insulation you use?
i'm not that familiar with insulation..but what about wall insulation? thats REALLY thick would that work at all?
and should you wrap the insulation in some kind of plastic to seal it off? insulation fibers=unhealthy to breath in?
i'm getting ready to build m ine..just wondering!!  |
Yes standard wall insulation will work, but you have to get it pretty thick for standard pink fluffy insulation to work well low in the band. Its not really about density but a related physical property called gas flow resistance that has a linear relationship [of a given material the higher the density, the higher the GFR].
Going from 4" to 24" thick with a higher GFR material like 705 or dense flavors of rockwool gives little reward for all the extra expense. About 4" is the "sweet spot' for efficeincy with such materials.
Using only 4" of a lower GFR material like roll insulation will not work on LF - but 24" of it will perform superlatively all the way across the band.
Mineral wool is not a health risk - but it is a nasty irritant - any breathable fabric cover will do to keep you away from it and vice versa - use the poly film if you want to reject HF as described above.