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What's the Best Type of 'Green' Insulation?

2/1/2009 12:00:00 AM

Tags: insulation, green insulation, home insulation

What’s the best choice for “green” insulation in the new addition to our house?

Lillian Kirby
New York, New York

There are several good alternatives to fiberglass insulation if you want a “green” product to insulate the addition. 

Insulation made from recycled denim is treated with a fire retardant. It’s not made of used fabric but scraps from the manufacturing process. In general, growing cotton is tough on the environment because of the heavy use of pesticides, so this may not be the best option, although it’s a good use of otherwise wasted material. 

Wool insulation provides an option that is natural and renewable. Although wool is flame resistant naturally, it is subject to insect damage. So the insulation is usually treated with boron to deter insects. But boron is a naturally occurring element and not known to be carcinogenic. 

Cellulose insulation is probably your best bet. It’s made from 80% recycled newspaper, and the chemicals that hold it together do not use formaldehyde. Fire-retardant chemicals are also necessary to make the product safe. R-values of fiberglass, wool cellulose are similar, but can vary significantly based on a number of factors. Cellulose insulation is more affordable than wool insulation, too. 

Don’t overlook Structural Insulated Panels (SIPs) as an option for building the new addition. SIPs are basically slabs of polystyrene sandwiched between two sheets of oriented strand board (OSB). Because the polystyrene allows very little air to pass through the walls, they produce a super-insulated structure.

— Troy Griepentrog, senior associate editor

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12/22/2011 5:46:52 PM
There are a ton more products that are not listed here. Poly is an amazing product. I would also look heavily in to ICF and I-Form. Plus a good insulation machine to blow cellulose or fiberglass.

6/26/2011 2:48:19 PM
Some additional, and exclusive benefits of wool insulation include: its ability to absorb and release moisture, which maintains a constant inside temperature much more effectively than other products; its resiliency - it does not break down over time improving insulation effectiveness and making it much more cost efficient over the long term as it will last the lifetime of the home; requires only a fraction of the energy needed to manufacture other "green" insulations; and, it absorbs and breaks down indoor air pollutants, including formaldehyde, nitrogen dioxide, and sulphur dioxide improving indoor air quality and helping to prevent related health problems. Not to mention, sheep' wool insulation is less cost-prohibitive today as compared that of the writing of this article. Please consider revising your comparative analysis as this product is the elite earth-friendly insulation. I will gladly provide you with the sources of my information as well, just email me!

6/28/2010 6:58:58 AM
natural fibers such as kenaf are also of interest for green insultation as their culture does not compete with food crops... in addition, their application does not generate any dust

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