Keeping Warm and Staying HealthyA Comprehensive look at Fiberglass and Cellulose Insulation

Natural Resources Defense CouncilPrincipal Author and Researcher: Anjanette DeCarlo; Project Design and Direction: Allen Hershkowitz

INTRODUCTIONInsulating a home or office is one of the easiest and most cost effective things to do to protect the envi-ronment. As we all know, insulation reduces the amount of energy required to heat or cool a space. Whatis less well known is that there is a variety of different insulating materials with a range of environmentalattributes, costs, advantages, and disadvantages.

Just because insulation helps conserve energy does not mean that the product itself is environmentallysound, many other factors must be considered when assessing the product’s environmental soundness,including the health risks, energy required to produce the insulation, its flammability and its recycledcontent. The Natural Resources Defense Council (NRDC) report examines fiberglass and cellulose insulation materials.

SUMMARY OF FINDINGS

After careful review of the literature, interviews with insulation industry executives, government officials,academics and scientists as well as site visits to manufacturing facilities associated with the materialsstudied, the NRDC has concluded the following:

* Cellulose insulation manufactured from recycled paper is the least polluting and most energyefficient.

* Cellulose has the highest post-consumer recycled content. The fiberglass industry averages 35%recycled glass, while the cellulose industry averages a minimum of 75% recycled content.

* It takes more than 10 times more energy to produce fiberglass insulation as cellulose insulation.

* Due to air circulation and natural convection, the R-value of blown in fiberglass insulation decreases by as much as 50% as the temperature drops from 45o degrees Fahrenheit to 18o

degrees Fahrenheit.

* In contrast to fiberglass, cellulose has a better resistance to air flow and prevents the upward movement of air caused by temperature differences {the R-value of Cellulose actually improves during cold weather}. Heat flow problems associated with fiberglass make cellulose an attractive alternative.

* Substantial and well-documented public health threats are associated with fiberglass. Fiberglass insulation is required to carry a cancer warning label in compliance with OSHA’s Hazard Communication Standard.

* No adverse health effects from cellulose insulation have been identified.

* Both types of insulation meet the American Society for Testing Materials (ASTM).

Due to air circulation and natural convection, the R-value of blown in fiberglass insulation, gdecreases by as much as 50% as the temperature drops from 45o degrees Fahrenheit to 18oydegrees Fahrenheit.

* In contrast to fiberglass, cellulose has a better resistance to air flow and prevents the upward g , p pmovement of air caused by temperature differences {the R-value of Cellulose actually improves y p { yduring cold weather}. Heat flow problems associated with fiberglass make cellulose an g }attractive alternative.

CAN-CELL INDUSTRIES INC.14735 - 124 Avenue, Edmonton, AB T5L 3B2

Ph: (780) 447-1255 Fax: (780) 447-1034 1-800-661-5031MANUFACTURER AND DISTRIBUTOR OF BUILDING MATERIALS AND HARDWARE PRODUCTS

REFERENCE # 3.4 APR 05

Knowledgeable building owners know there is more toinsulation performance than the laboratory R-valueprinted on the bag.

R-Value measurements of insulation do not includeenergy losses due to air leakage, convective loops withinthe wall membrane, or gaps and voids commonly foundin walls insulated with batt material. Batt type insulationsare often unable to conform to actual wall constructionbecause they are designed to fit an exact spacingbetween structural members. They must be cut, torn,compressed or otherwise deformed in order to fit into anyirregular shaped space. Obstructions in the walls such aswiring, plumbing or blocking further impair properplacement of these prefabricated insulations. Suchimperfections result in enough increased air infiltration toreduce thermal performance by as much as 30-50%below the laboratory R-value published by the insulationmanufacturer.By contrast, the WallBAR laboratory R-value and thefield performance R-value is identical. There are twomain reasons why WallBAR performs better in an actualbuilding. First, because the material is injected intoposition, it forms a seamless, void free fit, conformingskin tight to all obstructions and irregularly shapedcavities. By thus eliminating the usual channels of airleakage within wall cavities, substantial reduction in heatloss and moisture accumulation may be achieved.

Second, air movement through WallBAR is less thanthat through glass batt because the fibrous mass ofWallBAR is considerably more dense and, unlike glassfibre where insulating value is dependent on unstable airpockets formed between solid fibres, much of theinsulating air in the WallBAR system is sealed within thecellular structure of its natural wood fibres. It is thephysical difference between these two types of fibrewhich gives WallBAR both high R-value and superiorresistance to the convective air movement that degradesthe field performance of glass batt insulations.

When comparing WallBAR to glass fibre batt, do not limitconsiderations to rated R-value and installed cost.WallBAR is perceived to be more expensive than batts,but its more effective performance when winter windsblow ensures that it is very competitive. A majortechnical university in the USA recently published resultsof a study of insulation efficiency and air leakage. Toparaphrase their findings, effective insulation must havethree essential aspects:R-VALUE, THERMAL MASS, and the ability to INHIBITINFILTRATION. Glass fibre batts possess R-Value but

are deficient in the other aspects. WallBARincorporates all three properties. That makes thissystem a good deal for both the builder and the buyer.A lifetime of reduced energy costs and increasedcomfort are long term advantages most people willhappily settle for.

Some of the most frequently asked questions aboutWallBAR are as follows:

What is WallBAR?WallBAR is manufactured to the same demandingcriteria as WEATHERSHIELD Loose-fi l l . I t ismanufactured from 100% recycled wood fibre, andcontains a dry adhesive component which ultimatelyforms a cohesive blanket in the wall cavity. It is fireresistant and safe to use.

How is the material Installed?Application is done by injecting insulation into cavitiesformed by stapling a netting over the face of the framingtimbers. The operator is thereby able to form acustomized matt of material which conforms to anyshape of cavity or obstruction.

Is moisture added?WallBAR is normally injected dry, but moisture can beadded, as an option, during installation. 10% moistureby weight, which is well below the amount permitted inframing lumber, will begin to activate the adhesivebinder to form a homogeneous blanket in the wall.

What is the density and texture ofWallBAR?WallBAR is injected into wall cavities at a density ofabout 2.75 lbs / ft3. The material will eventually form acohesive matt behind the mesh, due to the naturalmigration of moisture in and out of the wall, whichactivates the dry adhesive.

What about air leakage?A principal advantage of WallBAR over conventionalglass fibre batt is that WallBAR completely fills eachstud cavity, forming a substantial barrier to the usualpaths of air leakage. Not only are there no voids forconvective air currents to follow but the leak points atthe interface of sheathing and plates are effectivelysealed.

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WallBAR“The High Performance Wall Insulation System”

R-Value measurements of insulation do not includeenergy losses due to air leakage, convective loops withingy g , pthe wall membrane, or gaps and voids commonly found, g p yin walls insulated with batt material. Batt type insulationsypare often unable to conform to actual wall constructionbecause they are designed to fit an exact spacingy g p gbetween structural members. They must be cut, torn,y , ,compressed or otherwise deformed in order to fit into anyp yirregular shaped space. Obstructions in the walls such asg p pwiring, plumbing or blocking further impair properg, p g g p p pplacement of these prefabricated insulations. Suchp pimperfections result in enough increased air infiltration top greduce thermal performance by as much as 30-50%p ybelow the laboratory R-value published by the insulationmanufacturer.By contrast, the WallBAR laboratory R-value and they , yfield performance R-value is identical. There are twopmain reasons why WallBAR performs better in an actualy pbuilding. First, because the material is injected intog , jposition, it forms a seamless, void free fit, conformingp , , , gskin tight to all obstructions and irregularly shapedg g y pcavities. By thus eliminating the usual channels of airy gleakage within wall cavities, substantial reduction in heatg ,loss and moisture accumulation may be achieved.

REFERENCE # 3.4 APR 05

WallBAR“The High Performance Wall Insulation System”

What about wood rot and fungal growth?Any wall which leaks air provides an opportunity for freewater to form as a result of condensation. Water formingin a glass fibre insulated wall will run downward under theforce of gravity and pool along the bottom sill plate. Undersuitable temperature and moisture conditions both moldand wood rot fungi will flourish. WallBAR solves thisproblem completely –first, by virtually eliminating the con-vective air leakage which is the cause of moistureformation and second, any water that might be driven intoa WallBAR wall cavity will be absorbed by the WallBARmatt and transported by wicking action to a surface whereevaporation can occur. Even if moist conditions were topersist for a period of time the borates within WallBAR actas an effective fungicide to prevent growth of fungus orforms of insect life.

How soon may drywall be applied?Drywall may be installed immediately following installationof WallBAR. In three instances where walls of test houseswere opened for inspection one year after the installationof WallBAR, the framing lumber, sheathing, drywall andinsulation were all found to be in a sound, dry condition. Intwo of these homes the wall areas inspected had beendrywalled less than 24 hours after the insulation wasinstalled.

What about application under freezingconditions?The only restriction on low temperature is the practicalaspect of operating a water spray system at belowfreezing temperatures. This can be overcome in part byusing warm water and a circulating pump system. There isno problem with respect to the WallBAR material freezingin the wall. Field trials of three houses fitted with electronicsensing gear indicate drying action continues duringwinter months. Some moisture is thought to evaporate intothe interior of the heated structure and some is removedby sublimation through the frozen exterior.

What about comfort?We are all familiar with discomfort caused by colddraughts during winter time. Even when no actual airleakage occurs, an uncomfortable sensation of leakageoccurs when body heat radiates to a cold spot on anexterior wall. By providing a fully insulated wall cavity,WallBAR guards against these discomforts.

What about noise?Whether your home is located in a high noise area ornot, sound from traffic, neighbors or animals candetract from the general level of home comfort.WallBAR adds a significant level of protection againstsuch unwanted noise.

What about environment?WallBAR is produced from select grades of recycledpaper, and it is produced by a process that requiresonly minor amounts of electrical energy. Because ofthe above features WallBAR carries EnvironmentCanada's *EcoLogo emblem, which is formaldesignation of an environmentally friendly product.

*The word ‘EcoLogo’ is an official mark of EnvironmentCanada.

What about economy?WallBAR insulation is economical because its superiorperformance gives you extremely good value for yourinsulation dollar. Your investment in WallBAR willprovide you with dividends year after year in reducedheating and cooling costs, plus the added benefit ofliving in a more comfortable draft free, quieter home.

Is the WallBAR System approved byBuilding Authorities?Yes. Alberta Building Standards has issued anapproval for use of spray applied WallBAR as athermal insulation for walls. WallBAR is also approvedfor use in buildings for which Canada Mortgage andHousing Corporation (C.M.H.C.) provides financing orloan insurance. CCMC Evaluation #12344R.

With WallBAR we are not talking theory. We aretalking field performance, as measured by numerousblower door air leakage tests and actual energyconsumption. The type of insulation you use in yourhome will have a significant effect on your home'senergy cost, and the overall level of comfort. The timeto determine what type of insulation you should haveis BEFORE construction begins.

Call (780) 447-1255 or 1-800-661-5031fax (780) 447-1034 for more information.

CAN-CELL INDUSTRIES INC.14735 - 124 Avenue,

Edmonton, AB T5L 3B2