FREE Encyclopedia of Building & Environmental Construction, Diagnosis, Maintenance & Repair The accuracy & trustworthiness of every article or Q&A is researched by human experts. See WHO ARE WE?
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.
- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?
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
R-value
Moisture absorption
Attraction to (resistance to) nesting rodents
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.
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.
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.
The link to the original Q&A article in PDF form immediately below is preceded by an expanded/updated online version of this article.
Q&A on Cellulose Pros & Cons - PDF version, use your browser's back button to return to this page. Original article, Solar Age Magazine, December 1985/January 1986, adapted and updated for InspectAPedia.com December 2010.
The question-and-answer article above, quotes-from, updates, and comments an original article from Solar Age Magazine and written by Steven Bliss.
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
Solar Age Magazine was the official publication of the American Solar Energy Society. The contemporary solar energy magazine associated with the Society is Solar Today. "Established in 1954, the nonprofit American Solar Energy Society (ASES) is the nation's leading association of solar professionals & advocates. Our mission is to inspire an era of energy innovation and speed the transition to a sustainable energy economy. We advance education, research and policy. Leading for more than 50 years.
ASES leads national efforts to increase the use of solar energy, energy efficiency and other sustainable technologies in the U.S. We publish the award-winning SOLAR TODAY magazine, organize and present the ASES National Solar Conference and lead the ASES National Solar Tour – the largest grassroots solar event in the world."
Steve Bliss's Building Advisor at buildingadvisor.com helps homeowners & contractors plan & complete successful building & remodeling projects: buying land, site work, building design, cost estimating, materials & components, & project management through complete construction. Email: info@buildingadvisor.com
Steven Bliss served as editorial director and co-publisher of The Journal of Light Construction for 16 years and previously as building technology editor for Progressive Builder and Solar Age magazines. He worked in the building trades as a carpenter and design/build contractor for more than ten years and holds a masters degree from the Harvard Graduate School of Education.
Excerpts from his recent book, Best Practices Guide to Residential Construction, Wiley (November 18, 2005) ISBN-10: 0471648361, ISBN-13: 978-0471648369, appear throughout this website, with permission and courtesy of Wiley & Sons. Best Practices Guide is available from the publisher, J. Wiley & Sons, and also at Amazon.com
"Energy Savers: Whole-House Exhaust Ventilation Systems [copy on file as /interiors/Energy_Savers_Whole-House_Exhaust.pdf ] - ", U.S. Department of Energy energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11870
"Energy Savers: Ventilation [copy on file as /interiors/Energy_Savers_Ventilation.pdf ] - ", U.S. Department of Energy
"Energy Savers: Natural Ventilation [copy on file as /interiors/Energy_Savers_Natural_Ventilation.pdf ] - ", U.S. Department of Energy
"Energy Savers: Energy Recovery Ventilation Systems [copy on file as /interiors/Energy_Savers_Energy_Recovery_Venting.pdf ] - ", U.S. Department of Energy energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11900
"Energy Savers: Detecting Air Leaks [copy on file as /interiors/Energy_Savers_Detect_Air_Leaks.pdf ] - ", U.S. Department of Energy
"Energy Savers: Air Sealing [copy on file as /interiors/Energy_Savers_Air_Sealing_1.pdf ] - ", U.S. Department of Energy
Falls and Related Injuries: Slips, Trips, Missteps, and Their Consequences, Lawyers & Judges Publishing, (June 2002), ISBN-10: 0913875430 ISBN-13: 978-0913875438 "Falls in the home and public places are the second leading cause of unintentional injury deaths in the United States, but are overlooked in most literature. This book is unique in that it is entirely devoted to falls. Of use to primary care physicians, nurses, insurance adjusters, architects, writers of building codes, attorneys, or anyone who cares for the elderly, this book will tell you how, why, and when people will likely fall, what most likely will be injured, and how such injuries come about. "
FIBERGLASS HAZARDS Indoor Air Quality Investigations: Health Concerns About Airborne Fiberglass: Fiberglass in Indoor Air from HVAC ducts, and Building Insulation
The Stairway Manufacturers' Association, (877) 500-5759, provides a pictorial guide to the stair and railing portion of the International Residential Code. [copy on file as http://www.stairways.org/pdf/2006%20Stair%20IRC%20SCREEN.pdf ] -
WEATHER RESISTIVE BARRIERS [PDF] U.S. Department of Energy, ", how to select and install housewrap and other types of weather resistive barriers
In addition to citations & references found in this article, see the research citations given at the end of the related articles found at our suggested
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: info@carsondunlop.com. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
Carson Dunlop Associates provides extensive home inspection education and report writing material. In gratitude we provide links to tsome Carson Dunlop Associates products and services.