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Resources, Conservation and Recycling 86 (2014) 9–15

Contents lists available at ScienceDirect

Resources, Conservation and Recycling

jo ur nal home p age: www.elsev ier .com/ locate / resconrec

heep’s wool insulation: A sustainable alternative use for a renewableesource?

.W. Corscaddena, J.N. Biggsb,∗, D.K. Stilesb

Engineering Department, Dalhousie University, Faculty of Agriculture, P.O. Box 550, Truro, NS, Canada B2N5E3Rural Research Centre, Dalhousie University, Faculty of Agriculture, P.O. Box 550, Truro, NS, Canada B2N5E3

r t i c l e i n f o

rticle history:eceived 30 August 2013eceived in revised form 22 January 2014ccepted 23 January 2014

eywords:ool insulation

ustainable agriculturehermal propertiesuarded hot boxreen building productscale

a b s t r a c t

Material selection in manufacturing may be characterized as a series of trade-offs between characteristics,properties, environmental impacts, sustainability, availability, and economics. Societal concerns aboutthe environmental impacts of construction practices and materials have been expressed through anincrease in the demand, production and use of “green” building products. This, combined with a desireto integrate more bioproducts and natural and renewable resources into the construction industry, hasextended to the production and promotion of insulation made from sheep’s wool.

Although substantial literature exists on the insulation properties and other benefits of wool, less isknown about the economics and manufacturing processes of sheep’s wool insulation at varying scales ofproduction. This paper contributes to this field of enquiry through presentation of the preliminary resultsof a wool insulation manufacturing pilot project, in which the scale and economics of the production ofsheep’s wool insulation were considered. Processing techniques, the impact of sheep breed, yield, energyuse, and manufacturing costs were also examined. The results of the pilot project indicate that, whilesheep’s wool insulation produced at a smaller, or artisanal scale shows some potential, scale of operation

and volume of production need to be carefully considered in order to ensure long-term sustainabilityof the operation. Using the least expensive sheep’s wool available for the manufacture of wool battinsulation (and thereby reducing production costs) did not, in this pilot study, have a negative impact onproductivity or product performance. Diversion of this waste stream of currently less marketable, andconsequently less valuable wool, into the production of a green building material may offer small butsignificant benefit to sheep producers and the broader agricultural community, as well as consumers.

. Introduction

Sustainability and innovation have become the twenty firstentury drivers of responsible resource stewardship and materialtilization. The construction industry is no exception. Kibert (2008)uggests the following six areas as measures of sustainable buildingonstruction: reducing resource consumption, reusing resources,tilizing recycled materials, conserving the natural environment,emoving toxins, ensuring economic efficiency by considering lifeycle costs and reinforcing quality. Thus, to achieve sustainable orgreen” buildings, building design and construction are very mucht the leading edge of integration and application of innovativeechnologies and products. Such innovation has been encouraged

y governments, through, for example, the US Energy Indepen-ence and Security Act, and the European Energy Performance ofuildings directive, both of which encourage low energy or zero

∗ Corresponding author. Tel.: +1 902 893 6715.E-mail address: jaclyn.biggs@dal.ca (J.N. Biggs).

921-3449/$ – see front matter © 2014 Elsevier B.V. All rights reserved.ttp://dx.doi.org/10.1016/j.resconrec.2014.01.004

© 2014 Elsevier B.V. All rights reserved.

energy buildings. This has led to the development of energy perfor-mance certificates, energy star labels and programs such as LeadingEnergy and Environmental Design (LEED) certification (CanadaGreen Building Council, 2012). Ghaffarianhoseini et al. (2013) sug-gests building energy efficiency, thermal performance and materialefficiency be considered as three primary measures of sustainablebuildings. This increased awareness of sustainability issues glob-ally and the move toward sustainable buildings has resulted inthe appearance of a large number of “green” building products onthe market. “Green” building products run the gamut from roofshingles made from recycled tires to retaining walls, flooring anddecking made from recycled plastics; from permeable paving madefrom recycled glass or plastic, to natural indoor products such asflooring, wallboard, and insulation made from recycled pop bot-tles. Fibrous agricultural materials such as straw, flax, cotton andhemp have also been investigated as potential insulating products,

and all are examples of the move toward sustainable materialsin the construction of homes and other structures (Thompson,2006; Hemptechnology, 2013; Tradical, 2013; Cotton Incorporated,2013).

1 onservation and Recycling 86 (2014) 9–15

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Table 1Thermal properties of commercially available wool and other sustainable buildingmaterials.

Manufacturer Material RSI 25.4 mm(1′′) m2 K/W

EcoBatta Sand, recycled bottle glass 0.61Thermafleeceb 85% wool and 15% polyester 0.66Black Mountainc Wool 0.64WEKAd Wool 0.64Tradicale Hemp and flax 0.65UltraTouch Denimf Cotton 0.694Demilec Inc.g Recycled plastic, soy and mineral oils 1.05

a http://www.knaufinsulation.ca/en/content/ecobatt-glasswool.b http://thermafleece.com/.c http://www.blackmountaininsulation.com.d http://www.goodshepherdwool.com/pdf/weka.pdf.e http://www.tradical.com/hemp-lime.html.f http://bondedlogic.com/pdf/denim-insulation/ESR-1134.pdf.

0 K.W. Corscadden et al. / Resources, C

Bioproducts is a term used to describe materials derived fromustainable biological or natural resources. Sheep’s wool is oneuch bio-product that has demonstrated some potential and hasegun to be marketed and promoted as an alternative insulat-

ng material (Sheepwool Insulation, 2013a; Black Mountain, 2014).ool has many physical attributes that make it attractive as a

aw material for insulation, including strength, hydrophobic andydrophilic characteristics, thermal performance, and the naturalbility to regulate temperatures and fire resistance (Johnson et al.,003; Sheepwool Insulation, 2013a; Ye et al., 2006). Wool insula-ion can also be installed without protective clothing, since unlikeberglass, it generally does not cause irritation to the skin, eyesr respiratory tract (Sheepwool Insulation, 2013a). Wool is also aenewable resource, as the average sheep (excluding hair sheepreeds) produces between 2.3 and 3.6 kg of raw wool annually thatust be sheared (removed) for the health of the animal. The use ofool for building insulation in North America would appear to be aeans to create additional and more diversified markets for a valu-

ble resource. It follows that this sustainable material, convertednto a green building material, could provide additional incomeor sheep producers. Presently, sheep producers in some parts oforth America do not receive a sufficient price for their wool such

hat even the annual shearing costs have become a burden, as therice paid for the fleece, in certain instances, does not cover theosts of shearing and transport of wool fleeces to market (Stilesnd Corscadden, 2011).

Although wool itself is a renewable resource and in a life cyclessessment of natural and traditional acoustic materials, Asdrubalit al. (2012) found sheep’s wool to have one of the lowest environ-ental impacts, yet the sustainability of the actual manufacturing

rocess used to convert raw wool into insulation is still unknown.his paper examines the sustainability of wool insulation produc-ion through a case study that examined the manufacturing processsed to process raw wool into wool insulation on an artisanal scale.

previous research project conducted by the team had shown thatnly approximately 45% of the region’s annual wool production isurrently being marketed (with the remainder being stockpiled oriscarded on the farm) (Stiles and Corscadden, 2012). The goals ofhis pilot project were to identify steps essential to the manufac-uring process, monitor the processing technique, and examine thempact of sheep breed/breed mixture on the manufacturing opera-ion. Manufacturing costs and material properties produced by therocess were quantitatively measured. Energy demand, yield, andubsequent thermal insulating properties for the wool insulationroduced were also measured. A time and motion study was usedo assess the economic feasibility of the artisan-scale, wool battroduction facility pilot project based at Harmeny Woolen Mill inentral North River, Nova Scotia, Canada.

The existing literature on insulation materials and their proper-ies extends to the mid- to late twentieth century (see, for example,larke and Yaneske, 2009; Fournier and Klarsfeld, 1974; Gravesnd Yarbrough, 1992), but did not address the use of sheep’s woolor insulation. More recent research has investigated alternativeuilding materials such as cotton stalk fiberboard (Zhou et al.,010) and the diversion of waste streams for insulation, such as theonversion of elastomeric waste residues (Benkreira et al., 2011).n a study related to European building envelopes, Papadopoulos2005) reported that the thermal properties of many commonlyvailable insulating materials, such as fiberglass, rock wool, perlitend expanded polystyrene were similar, although significant differ-nces in material characteristics were nevertheless apparent. Theseifferences include cost, fire resistance and the ability of material

o absorb water. Liang and Ho (2007) identified that the toxicityf insulating materials such as rock wool and fiberglass are sig-ificantly higher when combusted than was the case with organicaterials. Jerman and Cerny (2013) investigated the impact of heat

g http://www.demilec.com/english/heatlok-soya-builders.

and moisture on insulating materials and identified that the ther-mal conductivity of mineral wool has a positive correlation withmoisture content, which results in a significant reduction in ther-mal insulation properties for a relatively small increase of 5–20%moisture content.

The use of alternative materials, particularly sheep’s wool,can still be considered an emerging research topic, as publishedresearch tends to focus on the thermal values of wool insulationin comparison to conventional insulating materials. An Australianstudy conducted by Symons et al. (1995), for example, comparedthe thermal conductivity in relation to density and thickness forfiberglass, wool, polyester and cellulose fibers insulating materi-als in both loose fill and batt forms. They concluded that fiberglassbatts require less thickness than sheep’s wool at any particular den-sity to achieve target thermal resistance values, as sheep’s wool isa highly variable material and insulation density is insufficient toaccurately predict thermal performance (Symons et al., 1995). Astudy based on material produced in New Zealand reports woolhaving similar properties to fiberglass but that wool also isolatesvibrations, reducing the sound index by up to six decibels (Ballagh,1996). Desarnaulds et al. (2005) also found sheep’s wool to haveequal of better sound absorption than mineral wool. Johnson et al.(2003) identified another potential use for sheep’s wool, as a techni-cal fiber, due to wool’s unique physical attributes. A study involvingresearch conducted in New Zealand and Northern Ireland examinedalternative forms of insulating material and found that hemp andsheep’s wool with comparable densities produce similar rates ofthermal conductivity (Ye et al., 2006).

An example of the thermal resistance values of wool and other“sustainable” materials is listed in Table 1.

Zach et al. (2012) evaluated ecological insulation materials andreported that sheep’s wool has many advantages, including hygro-scopicity and fire resistance. Their findings were in agreement withfindings presented by Symons et al. (1995). Zach et al. (2012) alsoreported that the bulk density of wool is inversely correlated to airflow in the pore structure of the insulation, such that increasingbulk density results in greater thermal insulating properties. Thisagrees with Ye et al. (2006) who also found that wool thicknessis positively correlated with thermal resistance, provided that thedensity was above 11 kg/m3. Symons et al. (1995) and Trethowen(1995) also reported similar results. Zach et al. (2012) support theconclusions presented by Ballagh (1996) that sheep’s wool is anexcellent acoustic material; however, they noted that no additionalacoustic benefit is achieved at material thickness of greater than

170 mm. The published literature in total argues the point thatwool has potential use as an insulation material yet many research

K.W. Corscadden et al. / Resources, Conservation and Recycling 86 (2014) 9–15 11

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uestions remain, including the economic viability and scaleequired for the sustainable production of sheep’s wool insulation.

Sheep’s wool insulation is commercially available in variousorms from a limited number of suppliers worldwide; however, itends to be more expensive than conventional insulating material.he current price (before taxes) of sheep’s wool insulation fromreland’s biggest retailer is $19.59/m2 CAD (Sheepwool Insulation,013b), for 10 cm thick insulation. The Good Shepherd, a Northmerican distributor of Black Mountain U.K. sheep’s wool insula-

ion, sells insulation in Canada by mail order for $20.99/m2 CADGood Shepherd, 2013). By contrast, fiberglass costs an average costf $4.63/m2 CAD (Kent Building Supplies, 2013). Sheep’s wool insu-ation is presently over four times more costly than conventionalberglass insulation. Despite this high retail price demand appearso be growing, as suggested by the emergence of a small num-er of suppliers in Australia, New Zealand, USA, Canada, Ireland,nited Kingdom and Europe. It is important to note, however, that

he majority of these suppliers are part of a global supply andalue chain dominated by large scale manufacturing processes, andherefore represent sustainability only in the sense of their using aenewable resource and providing an alternative insulating mate-ial to those consumers who can afford to purchase the productt its present higher price. Sheep producers are part of the supplyhain, with wool as a globally traded commodity in this context.

. Materials and methods

The equipment used at Harmeny Woolen Mill in the produc-ion of insulation in the form of wool batts was manufactured byelfast Mini Mills, of Belfast, Prince Edward Island, Canada (Belfastini Mills Ltd, 2009). Raw wool for use in producing the wool battsas obtained from three different breeds of sheep (Romanov, Suf-

olk, North Country Cheviot) and two different commercial breedixes (identified in the study as Commercial A and Commercial

). All raw wool was obtained from local producers in Nova Sco-ia. The wool provided was representative of the type of materialvailable not only in the province of Nova Scotia, but also more gen-rally the wool available in eastern Canada and the northeast andid-Atlantic U.S. Costs associated with manufacturing were calcu-

ated based on the results of a time and motion study of five keyanufacturing steps: tumbling, scouring (with chemical applica-

ion), picking, carding and felting. These steps are briefly describedelow:

1) Tumbling – mechanically rotating wool so that loose debris fallsfrom the fleece.

2) Scouring – the wash process. The soap and water methodinvolves washing the wool in hot soapy water to remove dirt,grease and dry plant matter from the fleece. Wool is rinsed atleast twice to remove all of the unwanted detritus, washed withsoap, and then rinsed a final time. The composition of woolfibers requires an application of boron to protect fibers from

pests. This is addition typically occurs during the rinsing processand consists of a borax solution, such as disodium octaboratetetrahydrate, which is added at a rate of 3% of the weight of theinsulation batt (Murphy and Norton, 2008).

turing wool insulation batts.

(3) Picking – the separation of wool fibers, by opening the locks toallow for further processing.

(4) Carding – “combs” the fibers into the same direction, to createa wool batt. Any remaining dry plant material should fall outduring this step. This was the slowest step in the manufacturingprocess, after scouring.

(5) Wet felting – this process uses moisture and friction to essen-tially mat the wool fibers together to create an even more densematerial.

Two different types of batts were manufactured: a “carded” batt,which required the first four steps in the manufacturing process,and a “felted” batt, which utilized all five steps in the manufactur-ing process. Fig. 1 highlights the steps within the manufacturingprocess. The dimensions for both the carded and felted battswere 0.6096 m × 1.2192 m × 0.0889 m (2′ × 4′ × 3.5′′) and weight of0.4 kg/unit.

Each of the processing steps was assessed to determine the yield,waste, processing time and throughput, energy use, labor and waterrequirements and ultimately total manufacturing costs. A “Fluke43B” power analyser was used to measure electrical energy usefor each manufacturing step. The Fluke 43B was connected to theelectrical panel and costs were calculated based on a residentialrate in Nova Scotia of $0.13/kWh (Nova Scotia Power, 2012). Thecost of the water used during the scouring process was calculatedbased on the manufacturer’s specifications for water volume, plusthe cost of water heating using a propane heater.

Thermal conductivity, k (N America) or � (Europe) is typicallyused to characterize the insulation properties of a material. Ther-mal conductivity is expressed in units of watts per meter degreekelvin (W/mK) and may be expressed as thermal resistance (RSI)by dividing the material thickness (m) by the thermal conductiv-ity producing RSI (m2 K/W). A standard calibrated hotbox method,ASTM C1363 (ASTM International, 2013) was used in this casestudy to test thermal conductivity of the insulation batts produced.A hotbox was built in accordance with ASTM C1363. The hotboxhas outer dimensions of 1.24 m × 1.32 m × 2.46 m, with wall studsplaced 40.64 cm (16′′) on center and uniformly insulated using twosheets of extruded polystyrene, 5 cm (2′′), and 3.8 cm (1.6′′) thickto provide a combined RSI value of 3.08. A layer of vapor barrierwith acoustic sealant was applied to all internal surfaces to pre-vent extraneous air leaks. The box was divided using a test wall(in which the test material would be inserted) to create two cham-bers, the hot side known as the metering chamber, and the coldside known as the climatic chamber, Fig. 2.

A 200 W heating element was installed in the metering chamberand a selection of Type-T thermocouples installed in each chamber,which were evenly distributed at different heights (high, medium,low) along the central axis of each chamber, Fig. 3. The wires fromthe thermocouples were attached to a CR23X data logger locatedon the top of the apparatus and all holes created for the routing ofthe wires sealed using calking. Finally, a removable door was con-

structed using two 5 cm (2′′) pieces of extruded polystyrene (with acombined RSI value of 3.5) attached to a plywood sheet. These weresecured to each other using caulking as well as screws equippedwith insulation washers.

12 K.W. Corscadden et al. / Resources, Conservation and Recycling 86 (2014) 9–15

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Table 2Comparison of electrical costs for the production of one felted and carded unit.

Material Total energy (kWh/unit) Time (h/unit) Energy costs ($/unit)

ig. 2. Photograph of hot, metering chamber, climatic chamber and test wall.

The hotbox performance was tested using fiberglass insulationaterial with a known RSI value, which was tested for 15 repeti-

ions and resulted in an error of less than 2%. A Fluke 43B powereter was used to measure the steady state power of the hotbox

nd net energy use Q was calculated based on the differential tem-erature between the metering and climatic chambers (separatedy the test material for a given area) in Eq. (1). The results of ther-al conductivity tests are based on the average of five repetitions

f each wool sample under ambient conditions of 20 ◦C.

SI = A�T

Q(1)

here RSI is the thermal resistance (W/m2 K), A the specimen wallrea (m2), �T the temperature differential, and Q the net energyse.

Five carded insulation batts per sample were manufactured, andne felted batt per sample was also manufactured to determine ifarded or felted batts had variances in thermal performance. Theollowing section highlights the results of the time and motion

Fig. 3. Photograph of Type-T thermocouples and datalogger.

Felted 7.56 3.84 1.01Carded 7.41 3.67 0.99

study, including the costs of processing and evaluation of manu-facturing viability, as well as the thermal performance of the woolinsulation batts by breed/mix sample.

3. Results

The time and motion study was based on the production of a0.4 kg (1 lb) insulation batt for each sample. Processing time andenergy were not at all impacted by the different breeds or breedmixes and therefore the energy use and time required for each pieceof equipment to produce a 0.4 kg batt, presented in Fig. 4, are basedon the average results for all five breeds/samples. The yield was alsoconsistent from each sample, averaging around 40% loss, by weight,which is substantial, with the vast majority of this loss resultingfrom the scouring process.

The total cost of processing one insulation batt or unit was cal-culated using current residential electricity rates in Nova Scotia, of$0.13/kW h. The resultant costs for both felted and carded batts arelisted in Table 2, which shows only a $0.02 difference between thetwo processes.

Another major cost in the manufacturing process relates to theamount of water used during scouring. The process uses on average,454 L or 0.453 m3 of water per wash cycle. It was possible to wash 12units of wool per wash cycle, therefore a cost per unit for scouringcan be determined using Eq. (2), based on water costs of $0.80/m3.

0.453m3/cycle × 0.80m3 × 1 cycle/12 units = 0.03/unit (2)

The current price paid per kilogram of wool in Atlantic Canadavaries between $0.99 and $2.20, depending on the wool’s quality,breed of origin, and application/use. For low-grade wool destinedfor conversion into insulation, a cost of $1.32 per kg is assumed.Based on manufacturing losses of 40%, the post waste cost of rawmaterial was $1.00 per unit. Thus, the three main manufactur-ing costs per unit of wool insulation include raw material (wool),electricity and water. The labor cost component is impacted bythe throughput of the equipment. Each piece of equipment hasa different operating time and production capacity; therefore, todetermine accurate and realistic labor costs, a parallel manufac-turing maximum production capacity needs to be employed. Theparallel strategy therefore assumes that all pieces of equipment areoperated simultaneously for eight hours per day, with the through-put restricted by the piece of equipment with the lowest productioncapacity. Fig. 5 presents the number of batts or units that could beproduced daily, for each piece of equipment.

If the mill is operated in parallel, then the maximum productioncapacity, based on one piece of equipment for each task, is limitedby the minimum quantity that can be produced by a single pieceof equipment. In this case the picking and carding operations havethe lowest throughput at 0.4 kg per 22 min and 20 min, respectively,resulting in a maximum output of 24 units in an 8 h day. The totalproduction costs, inclusive of labor, are based on this productionvolume for an artisan scale operation. Labor was calculated basedon minimum wage rates in Nova Scotia of $10.15 CAD per hour.Since felting did not add any significant value to the insulation prop-erties, the total estimated production costs for the manufacturing

process have been based on carded insulation batts only. Table 2highlights these costs.

The results in Table 3 demonstrate that the variable costs asso-ciated with the manufacturing of wool insulation are $5.67 per

K.W. Corscadden et al. / Resources, Conservation and Recycling 86 (2014) 9–15 13

Fig. 4. Average power consumption, processing time and en

Table 3Production costs per unit for carded wool batt insulation.

Operation Cost ($/unit)

Material 1.00Labor 3.38Electricity 0.99

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Water 0.03

Total 5.67

nit (0.4 kg finished product). These costs do not take into accountny expenditures associated with equipment capital, maintenance,uilding rental, interest, advertising or miscellaneous costs, andherefore only represent the manufacturing portion of costs asso-iated with the production of wool insulation. Testing of thermalroperties allowed for determination of thickness required tobtain certain R-values.

The average thermal properties test results for each of the fiveamples was obtained using standard test method ASTM C1363ASTM International, 2013) and are listed in Table 4. The resultsndicate that only slight differences in thermal insulation values

Fig. 5. Production limitations for each manufacturing

ergy requirement to produce a 0.4 kg batt (one unit).

and material density were apparent between the sample breedsand sample commercial mixed breeds.

Table 4 lists the RSI, R values and density of wool insulation dif-ferentiated by breed. The results confirm that wool insulation hasRSI values which exceed the minimum required by the Nova Scotiabuilding code, currently published at R3.5 or 0.56 (RSI) per 25.4 mm(1′′) for walls adjacent to unconditioned space (Province of NovaScotia, 2011). The performance of wool insulation is comparable tovalues reported in the literature and hence for other materials suchas fiberglass, polystyrene and cellulose insulation.

4. Discussion

The results of the pilot project suggest that sheep’s wool insu-lation could compete with insulation types already available in themarketplace, if it can be produced at an economically sufficient and

feasible scale. Sheep’s wool is a sustainable, natural resource whoseinherent characteristics, as outlined above, make it attractive as aninsulating material. Additionally, the creation of a wool insulationindustry could provide an alternative use for a resource presently

step, based on an operational time of 8 h daily.

14 K.W. Corscadden et al. / Resources, Conservation and Recycling 86 (2014) 9–15

Table 4Thermal resistance (RSI), R values and density of wool insulation for five breeds.

Material properties Romanov Suffolk North Country Cheviot Commercial A Commercial B

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RSI (m K/W) 0.56 0.5932

R value 25.4 mm (1′′) 3.5 3.7

Density (kg/m3) 22.1 22.7

nderutilized or functioning only as part of the waste stream inertain parts of the world. The results of thermal insulation testsndicate slight differences in the insulation properties of each sam-le; however, the insulation produced by all samples tested in thistudy exceed existing Canadian building codes for thermal proper-ies. The manufacturing process involved three major costs: labor,

aterial and electricity, with material costs significantly impactedy the 40% losses identified as part of the manufacturing process.

The results presented in Table 3 are based on measured costs foraterial, yield, electrical, water use and labor. The results provide

n estimated manufacturing cost of $7.75/m2. The retail price ofther wool insulation suppliers at $19.59/m2, creates a slim mar-in of only $11.19/m2, without taking into account capital costs,hipping, distribution, marketing and margin for retailers. Even if

direct sales strategy were employed, the costs described in thistudy raise questions about the economic viability of the scale ofroduction used for this case study. The outcomes of the case studyo however indicate that breeds selection, albeit somewhat limited,oes not impact the thermal properties, yield or processing time.he main processing constraint however, is determined by theicker and carder machines, resulting in a maximum of 10.88 kgroduced per 8 h day. Assuming 260 days of operation per year, theotal output of finished product is estimated at 2829 kg (assuming

40% loss).

. Conclusions

This artisanal scale case study had as its goal to identify the opti-al processing requirements, manufacturing criteria and product

erformance of wool insulation based on the study of five differentreeds/breed mixes commonly found in Nova Scotia, Canada andhe region. The results indicate that although wool is competitiveith other insulation products in terms of thermal properties and

ffers other potential natural and economic development benefitsn its use, the volume of production required, based on physical testata, suggest that a multi-equipment process may be necessary. A

arger processing volume may also be required in order to makehe manufacturing at such a scale more sustainable over the longerm.

This study also determined that using the cheapest wool avail-ble for manufacturing the insulation – in this case, wool in thetlantic Canadian Province of Nova Scotia that is currently under-tilized, if used and not stockpiled/disposed of – would not have

negative impact on the productivity of wool insulation or prod-ct performance, based on the samples and the equipment used inhis study. Arguably, such use, would also not impact the textilendustry, given that the textile industry’s specific requirements forber and cost are negotiated on a global, rather than a regional orational basis (Stiles and Corscadden, 2012). The greatest cost iden-ified in Table 3 is labor; therefore, a more automated process mayesult in a more cost effective outcome, but appropriate scale is theey factor. Thus, sheep’s wool does have the potential to be devel-ped into a sustainable, natural and renewable insulation material,

ne that perhaps could service local, regional, or niche markets.urther research is required, however, to determine the optimalanufacturing process at varying scales of production. Such workay offer added benefits to the agricultural and wider community

0.6101 0.6146 0.62783.8 3.8 3.893 21.9 22

and for farm sustainability where the sheep production sector isconcerned.

Acknowledgments

The authors gratefully acknowledge the research collaborationprovided by Ruth and Greta Mathewson of Harmeny Woolen Mill,Central North River, Nova Scotia; Co-op students Jamie Creelmanand Ovide Mazerolle; funding provided by the Nova Scotia Depart-ment of Agriculture, Energy Pilot Program; Farm Energy Nova Scotia(FENS) and the Rural Research Centre of the Dalhousie UniversityFaculty of Agriculture (formerly, the Nova Scotia Agricultural Col-lege) for research facilities and support.

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