InspectAPedia®   -   Search InspectApedia

Cellulose insulation in the hand Pros and Cons of Cellulose Building Insulation

Cellulose building insulation advantages and disadvantages:

This article compares the features of loose-fill or blown-in cellulose building insulation with fiberglass and rock-wool loose-fill or blown-in materials.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Pro's and Cons of Cellulose Insulation

The question-and-answer article below paraphrases, quotes-from, updates, and comments an original article from Solar Age Magazine and written by Steven Bliss.

Question: How does Cellulose Insulation Stack Up Against Fiberglass or Rockwool Insulation?

I plan to retrofit 7 inches of blown insulation over the top of 6 inches of existing fiberglass insulation, and I would like to use blown-in cellulose.

How does cellulose insulation stack up against fiberglass or rockwool with respect to

  1. R-value
  2. Moisture absorption
  3. Attraction to (resistance to) nesting rodents
  4. Fire protection (fire resistance)

Thanks - David Stingle, Black Creek WI

Answer:

The R-vale per inch of loosefill insulation varies depending on its installed density and product characteristics. For that reason, the most reliable way to buy loose-fill insulation is to specify the R-value - not the thickness - and install the correct number of bags per square foot, following the loose-fill or blown-in insulation coverage chart printed on all insulation bags.

The insulation chart also shows a minimum insulation thickness necessary to guarantee the desired R-value3.

The U.S. Federal Trade Commission (FTC) requires insulation manufacturers to make available to consumers an information sheet explaining this system.

Moisture absorption of cellulose insulation: Of the three insulations you named: blown-in or loose-fill cellulose, fiberglass, or rockwool, only cellulose will absorb moisture, but this is only a problem if it gets drenched, such as by roof leaks into an attic or building wall. The other two insulations will hold moisture only on their glass or mineral fiber surfaces.

Fire resistance of cellulose insulation: Of the three insulation products we are discussing, only cellulose is potentially flammable, if its fire retardant loses effectiveness over time (as some suspect of the dry-applied fire-retardants). Studies in the mid 1980's of the reliability of fire retardance of cellulose insulation over time were inconclusive.

See Cellulose Insulation Fire Resistance for details.

As for rodent resistance of cellulose insulation, we (DJF) have observed that rodents are happy tunneling in just about any soft insulating material, but we have also observed that a different sort of pest, mold, is not generally found in cellulose insulation. We (DF) believe based on our own field and lab investigations that the fire retardant chemicals used to treat cellulose insulation appear to also resist mold growth.

Mold resistance of cellulose insulation: cellulose insulation appears to be resistant to mold growth. Details are
at Cellulose Insulation Mold Resistance

Watch out: other insulation properties such as air flow resistance and moisture resistance may be very important in some cases, such as choosing an insulation to use in or over a crawl space that may be damp, or against basement foundation walls - Ed.

See FIBERGLASS INSULATION MOLD for examples- Ed.

Details about the R-values and other properties of various insulation products can be found in our Insulation Table at INSULATION R-VALUES & PROPERTIES.

The link to the original Q&A article in PDF form immediately below is preceded by an expanded/updated online version of this article.

The question-and-answer article above, quotes-from, updates, and comments an original article from Solar Age Magazine and written by Steven Bliss.

Cellulose Insulation Articles


...

Continue reading at CELLULOSE INSULATION FIRE RESISTANCE or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

Suggested citation for this web page

CELLULOSE INSULATION PROS & CONS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to BUILDING INSULATION

Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia

Ask a Question or Search InspectApedia

Questions & answers or comments about cellulose building insulation

Try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

Note: appearance of your Comment below may be delayed: if your comment contains an image, photograph, web link, or text that looks to the software as if it might be a web link, your posting will appear after it has been approved by a moderator. Apologies for the delay.

Only one image can be added per comment but you can post as many comments, and therefore images, as you like.
You will not receive a notification
when a response to your question has been posted.
Please bookmark this page to make it easy for you to check back for our response.
Our Comment Box is provided by Countable Web Productions countable.ca

Comment Form is loading comments...

Citations & References

In addition to any citations in the article above, a full list is available on request.



ADVERTISEMENT