Building Smart: Fiberglass vs Cellulose
I've made it clear I'm not a huge fan of fiberglass insulation for a new home. My objection stems from how often I've seen poorly installed fiberglass insulation. Now I've come across a study performed by the University of Colorado School of Architecture. The idea was to test real world performance of cellulose against firberglass batts.
Two similar structures were built one with r-19 fiberglass insulation in the walls and r-30 fiberglass insulation in the attic, the other had r-19 cellulose insulation in the walls and r-30 cellulose insulation in the attic. The cellulose insulated building was seven degrees warmer after a nine hour heat loss test. More importantly, after three weeks of monitoring building performance the cellulose insulated building used 26.4% less energy than the fiberglass structure. The conclusion drawn was that the cellulose building performed 38% better than the fiberglass insulated building. Keep in mind both buildings had the same stated r-value. Keep a look out for effective r-value instead.
Two similar structures were built one with r-19 fiberglass insulation in the walls and r-30 fiberglass insulation in the attic, the other had r-19 cellulose insulation in the walls and r-30 cellulose insulation in the attic. The cellulose insulated building was seven degrees warmer after a nine hour heat loss test. More importantly, after three weeks of monitoring building performance the cellulose insulated building used 26.4% less energy than the fiberglass structure. The conclusion drawn was that the cellulose building performed 38% better than the fiberglass insulated building. Keep in mind both buildings had the same stated r-value. Keep a look out for effective r-value instead.
You've broken the 'filterglass' code - all insulations must trap air to do their job, cellulose and foam do, 'filterglass' is what air filter are made of!
Reply to this
Hi John,
Thanks for the comment. I'm glad someone performed this study. It's nice to see a hunch confirmed. My original objection to fiberglass insulation was it is easy to install poorly wasting energy dollars and degrading overall comfort. Anyway thanks again for the comment I look forward to hearing from you again.
Reply to this
Consider the alternative of recycled denim insulation. No VOCs, albost double the soundproofing, and resistance to mold and pests because of the borate-based fire retardent. An outreach video can be found at www.deniminsulation.net/video.html
Reply to this
Hi Nick,
I've heard of the denim insulation but I have no experience with it. How was the soundproofing determined?
If you would like to write a guest post on denim insulation that would be great. b
Reply to this