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Fire resistance of cellulose insulation:
This article illustrates and describes the fire resistant properties of cellulose building insulation materials. This document assists building buyers, owners or inspectors who need to identify building insulation materials and also people who need to recognize both asbestos materials (or probable-asbestos) in buildings as well as materials unlikely to contain asbestos - all by simple
In these articles we provide photographs and descriptive text various kinds of building insulation along with description of the characteristics of each material.
What is the Fire Resistance of Fire-Retardant Treated Cellulose Building Insulation?
Cellulose Fire Test No. - Home Depot sample
Anyone looking closely at cellulose insulation can often see recognizable bits of newsprint in this chopped fibrous gray insulating material. Walking through a major home improvement center recently we picked up some loose fill cellulose insulation that fell out of a package of new cellulose insulation being purchased by a client. Our photos (above) show what it looked like when we put a little of this insulation on a ceramic dish in the sink in our forensic lab.
We were curious to know how fire resistant this random sample of new cellulose insulation would be in response to a very simple test.
Watch out: DO NOT TRY THIS IN YOUR HOME - you could start a fire.
Using an ordinary butane cigarette lighter and in safe lab conditions over a sink with water and fire extinguishers at ready (Photo above left) we heated the cellulose insulation for 60 seconds in direct flame. The temperature to which we exposed our cellulose insulation sample was perhaps hotter than the insulation might experience if it were in contact with a light bulb, but possibly no hotter than if it were in contact with shorting electrical wiring or an overheating aluminum branch wiring circuit connection.
There was a very brief tiny flame as a piece of plastic-coated newsprint in the insulation caught fire. The plastic on this newsprint probably resisted treatment by the fire retardant chemical and that fragment burned easily - and momentarily. Other than that small fragment, the insulation charred, smoked, but would not support combustion.
Cellulose building insulation manufacturers should avoid accepting plastic or water-resistant coated papers into their insulation manufacturing process, or at least be sure that water resistant paper is present only at such trivial quantities (as indeed it was in our test sample) that the cellulose insulation will not support combustion after treatment.
Cellulose Insulation Fire Test No. 2, National Fiber Corp. (Cel-Pak & Nu-Wool)
Deborah Falkow, owner of MetroNY Insulation, provided us with a sample of cellulose insulation produced by National Fiber Corp. (Cel-Pak & Nu-Wool) for further testing in 2010. According Ms. Falkow, Cel-Pak and Nu-Wool have an 83% recycled content, primarily over-issue newsprint and other ground wood paper sources. The paper is fully fiberized (reduced to cellulose fiber) and infused with borate, a naturally occurring mineral. Borate gives cellulose [insulation] a Class A fire rating."
Watch out: DO NOT TRY THIS IN YOUR HOME - you could start a fire.
In our test lab we observed:
The National Fiber Corp cellulose insulation would not support combustion.
While the flame was applied the insulation fibers glowed, but when the flame was removed, immediately the combustion process stopped. Only traces of smoke were visible during the test.
Microscopic Comparison of Typical vs. "Fully Fiberized" Cellulose Building Insulation
Our photos compare sample of cellulose insulation collected from a Home Depot brand (below left) and National Fiber's "fully fiberized" cellulose insulation (below right). As you can see, fragments of newsprint remain recognizable in both samples (notice the "Y" and other letters at left and the "e" character at right.
But in our photos below, both taken at similar levels of magnification in the stereo microscope, the National Fiber Corp. cellulose was visibly much more fragmented into individual cellulose fibers. The number of discernable paper fragments per cubic centimeter was notably fewer than in the Home Depot sample.
Notice: although our lab and the author (DF) are trained in forensic microscopy, our forensic lab has no certification for fire testing or fire rating of materials. Judgment of degree of fiberization and remaining paper fragments, while obvious on direct physical examination, was nonetheless subjective because no quantitative fiber count nor count of particles by size was attempted.
In sum, our amateur "fire tests" demonstrated in two cases with two different cellulose insulation products (1. Home Depot brand, 2. National Fiber Corp. (Cel-Pak & Nu-Wool)) that our samples of new cellulose insulation would not support combustion. But take a look at NAIMA's findings just below.
NAIMA's Fire Resistance Testing of Cellulose Insulation
According to the North American Insulation Manufacturers' Association, the chemical treatment of cellulose insulation does not make cellulose insulation "non-combustible" nor does it prevent smoldering type ignition of the material. Cellulose insulation is tested for fire resistance using ASTM C-739.
It has also long been our opinion that the chemical retardant treatment, however effective it may be, may deteriorate over time or especially if the insulation is exposed to water - say from a roof or wall leak. NAIMA has a similar view.
But then, a chief competitor of cellulose insulation, fiberglass insulation products are also not exactly fireproof - the kraft paper to which lots of fiberglass insulation is affixed to ease installation (and provide somewhat of a vapor retarder), for example can be set afire and it is possible that some of the binder resins may support combustion.
ASTM C-665 is the test standard for fire resistance of mineral fiber batts and rolls, and ASTM C-764 is the fire test standard for loose fill mineral insulation.
In industry speak, fiberglass is considered a mineral fiber along with rock wool or mineral wool insulations.
Manufacturers of Cellulose Insulation
Some of the cellulose manufacturers registered by NIST include
National Cellulose Corp.,
National Fiber Corp. (Cel-Pak & Nu-Wool)
U.S. Insulation Sales Corp.,
Pal-O-Pak Insulation Company (aka National Cooperatives, Inc.),
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Asbestos products and their history and use in various building materials such as asphalt and vinyl flooring includes discussion which draws on ASBESTOS, ITS INDUSTRIAL APPLICATIONS, ROSATO 1959, D.V. Rosato, engineering consultant, Newton, MA, Reinhold Publishing, 1959 Library of Congress Catalog Card No.: 59-12535 (out of print).
Asbestos Identification and Testing References
Asbestos Identification, Walter C.McCrone, McCrone Research Institute, Chicago, IL.1987 ISBN 0-904962-11-3. Dr. McCrone literally "wrote the book" on asbestos identification procedures which formed
the basis for current work by asbestos identification laboratories.
Stanton, .F., et al., National Bureau of Standards Special Publication 506: 143-151
Pott, F., Staub-Reinhalf Luft 38, 486-490 (1978) cited by McCrone
ASHRAE resources on building insulation, dew point and wall condensation - see the ASHRAE Fundamentals Handbook, available in many libraries. The following three ASHRAE Handbooks are also available at the InspectAPedia bookstore in the third page of our Insulate-Ventilate section:
2005 ASHRAE Handbook : Fundamentals: Inch-Pound Edition (2005 ASHRAE HANDBOOK : Fundamentals : I-P Edition) (Hardcover), Thomas H. Kuehn (Contributor), R. J. Couvillion (Contributor), John W. Coleman (Contributor), Narasipur Suryanarayana (Contributor), Zahid Ayub (Contributor), Robert Parsons (Author), ISBN-10: 1931862702 or ISBN-13: 978-1931862707
2004 ASHRAE Handbook : Heating, Ventilating, and Air-Conditioning: Systems and Equipment : Inch-Pound Edition (2004 ASHRAE Handbook : HVAC Systems and Equipment : I-P Edition) (Hardcover)
by American Society of Heating, ISBN-10: 1931862478 or ISBN-13: 978-1931862479
"2004 ASHRAE Handbook - HVAC Systems and Equipment The 2004 ASHRAE HandbookHVAC Systems and Equipment discusses various common systems and the equipment (components or assemblies) that comprise them, and describes features and differences. This information helps system designers and operators in selecting and using equipment. Major sections include Air-Conditioning and Heating Systems (chapters on system analysis and selection, air distribution, in-room terminal systems, centralized and decentralized systems, heat pumps, panel heating and cooling, cogeneration and engine-driven systems, heat recovery, steam and hydronic systems, district systems, small forced-air systems, infrared radiant heating, and water heating); Air-Handling Equipment (chapters on duct construction, air distribution, fans, coils, evaporative air-coolers, humidifiers, mechanical and desiccant dehumidification, air cleaners, industrial gas cleaning and air pollution control); Heating Equipment (chapters on automatic fuel-burning equipment, boilers, furnaces, in-space heaters, chimneys and flue vent systems, unit heaters, makeup air units, radiators, and solar equipment); General Components (chapters on compressors, condensers, cooling towers, liquid coolers, liquid-chilling systems, centrifugal pumps, motors and drives, pipes and fittings, valves, heat exchangers, and energy recovery equipment); and Unitary Equipment (chapters on air conditioners and heat pumps, room air conditioners and packaged terminal equipment, and a new chapter on mechanical dehumidifiers and heat pipes)."
1996 Ashrae Handbook Heating, Ventilating, and Air-Conditioning Systems and Equipment: Inch-Pound Edition (Hardcover), ISBN-10: 1883413346 or ISBN-13: 978-1883413347 ,
"The 1996 HVAC Systems and Equipment Handbook is the result of ASHRAE's continuing effort to update, expand and reorganize the Handbook Series. Over a third of the book has been revised and augmented with new chapters on hydronic heating and cooling systems design; fans; unit ventilator; unit heaters; and makeup air units. Extensive changes have been added to chapters on panel heating and cooling; cogeneration systems and engine and turbine drives; applied heat pump and heat recovery systems; humidifiers; desiccant dehumidification and pressure drying equipment, air-heating coils; chimney, gas vent, fireplace systems; cooling towers; centrifugal pumps; and air-to-air energy recovery. Separate I-P and SI editions."
Construction Waterproofing Handbook, Michael T. Kubal. Quoting:
... an all-inclusive, project-simplifying guide for waterproofing and construction professionals. This comprehensive answer-packed resource is loaded with the up-to-date, clearly-defined information you need on every project, including work on the building envelope, below-grade, above-grade, and remedial waterproofing.
Brick Nogging, Historical Investigation and Contemporary Repair, Construction Specifier, April 2006. Historical use of brick in timber-framed buildings, drawing on the investigations of the Kent Tavern in Calais, VT.
"Brick nogging is a European method of construction which was brought to the new world in the early-nineteenth century. It was a common construction method that employed masonry as infill between the vertical uprights of wood framing." -- quoting the web article review.
"Energy Savers: Whole-House Supply Ventilation Systems [copy on file as /interiors/Energy_Savers_Whole-House_Supply_Vent.pdf ] - ", U.S. Department of Energy energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11880?print
"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
Fiberglass: Indoor Air Quality Investigations: Health Concerns About Airborne Fiberglass: Fiberglass in Indoor Air from HVAC ducts, and Building Insulation
Insulate & Weatherize (Taunton's Build Like a Pro), Bruce Harley. Review quoted:
An engineer who trains builders in energy-efficient construction, Harley offers a wealth of information that will allow readers to improve their home's efficiency, saving both money and natural resources. After an introductory section that explains the underlying principles of heat transfer, insulation, and air quality, Harley demonstrates basics such as weather-stripping and moves forward through advanced projects including insulation and major upgrades. Short "Pro Tips" as well as sections labeled "Trade Secrets," "What Can Go Wrong," and "In Detail" provide a great deal of helpful information. Increasing energy efficiency is one of the easiest ways for homeowners to save money
Insulation Types, table of common building insulation properties from U.S. DOE. Readers should see INSULATION R-VALUES & PROPERTIES our own table of insulation properties that includes links to articles describing each insulation material in more detail.
The National Institute of Standards and Technology, NIST (nee National Bureau of Standards NBS) is a US government agency - see www.nist.gov
"A Parametric Study of Wall Moisture Contents Using a Revised Variable Indoor Relative Humidity Version of the "Moist" Transient Heat and Moisture Transfer Model [copy on file as/interiors/MOIST_Model_NIST_b95074.pdf ] - ", George Tsongas, Doug Burch, Carolyn Roos, Malcom Cunningham; this paper describes software and the prediction of wall moisture contents. - PDF Document from NIS
Piquet Wall Construction: See this photo of
piquet wall construction - involving timber-framed wall construction with long top girts, diagonal timber bracing, and small diameter logs
placed vertically along with concrete chinking to fill in the wall plane.
Plank House Construction: weblog from plankhouse.wordpress.com/2009/01/25/plank-house-construction/ and where plank houses were built by native Americans, see
Large 1:6 Scale Plank House Construction / P8094228,
Photographer: Mike Meuser
06/12/2007 documented at yurokplankhouse.com where scale model Museum quality Yurok Plank Houses are being sold to raise money for the Blue Creek - Ah Pah Traditional Yurok Village project.
Principles of Heating, Ventilating, And Air Conditioning: A textbook with Design Data Based on 2005 ASHRAE Handbook - Fundamentals, Harry J., Jr. Sauer, Ronald H. Howell, William J. Coad. Quoting
... textbook for college level HVAC courses or independent study and review, especially when combined with the 1997 ASHRAE Fundamentals Handbook. Contains the most current ASHRAE procedures and definitive, yet easy to understand, treatment of building HVAC systems -- from basic principles through design and operation. Dual units of measurement.
Re-Bath, tub lining products is a bath tub relining manufacturer and distributor located in Tempe, Arizona - see rebath.com
Rubblestone Wall Filler: See this Lartigue House using exterior-exposed rubblestone filler between vertical timbers of a post and beam-framed Canadian building.
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: email@example.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides extensive home inspection education and report writing material.
The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors. Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
TECHNICAL REFERENCE GUIDE to manufacturer's model and serial number information for heating and cooling equipment, useful for determining the age of heating boilers, furnaces, water heaters is provided by Carson Dunlop, Associates, Toronto - Carson Dunlop Weldon & Associates Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on any number of copies of the Technical Reference Guide purchased as a single order. Just enter INSPECTATRG in the order payment page "Promo/Redemption" space.
The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume.
Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones