The energy efficiency of a building depends on building envelope performance.The results presented in this paper are the first of a long-term building envelope research project at the Alternative Village at the Univer...The energy efficiency of a building depends on building envelope performance.The results presented in this paper are the first of a long-term building envelope research project at the Alternative Village at the University of Manitoba in Winnipeg,Manitoba,Canada.Five test buildings were constructed using the following systems:two wood frames with fiberglass batt insulation and dense pack cellulose,one polyurethane structural insulated panels(PUR SIP),and two with the Stay in place PVC concrete form building system using 102mm and 204mm of concrete externally insulated with 102mm of expanded polystyrene foam.All of the buildings had a common foundation and roof system with a footprint of 23.8 m2.Blower door tests were conducted to determine air tightness.Each structure was heated with an electrical resistance heater and maintained at a constant internal temperature.The thermal gradient through the wall and power consumption were monitored.The study period discussed in this report represents the main heating season from October 2011 to April 2012 consisting of 209 days.Based on the power consumption,the PUR SIP consumed the least at 2498 kWh,while the 204 mm Stay in place PVC concrete form building used the most at 2898 kWh for the same time period.The thermal gradient through the cross section of the wood frame structures was compared through the cavity insulation and at the stud.It was found that the cellulose building provided better thermal resistance along the stud when compared to the fiberglass batt insulation.展开更多
The use of structural insulated panels(SIPs)for wall and roof assemblies in residential and commercial buildings is a well-known construction technique.SIPs typically use a combination of either expanded polystyrene f...The use of structural insulated panels(SIPs)for wall and roof assemblies in residential and commercial buildings is a well-known construction technique.SIPs typically use a combination of either expanded polystyrene foam(EPS)or polyurethane foam(PUR)as the core material.The covering or skin is predominantly oriented strand board(OSB).The OSB is either bonded to the foam with adhesive in the case of EPS,while polyurethane is used to provide adhesion with PUR SIPs.This paper presents the results of research that investigated the use of industrial hemp mat used as a skin for soy-based polyurethane foam panels.A series of tests were conducted to investigate moisture resistance and flexural behaviour on hemp mat foam panels.Moisture absorption behaviour was evaluated on three specimen types:uncoated,earth plaster and tung oil treated hemp mat.The absorption coefficient Aw was determined for all specimens.The tung oil treated specimens exhibited a water absorption coefficient that was 5.3%of that for untreated hemp mat panel specimens.Flexural tests were conducted on dry specimens with earth-plastered hemp mat,tung oil coated hemp mat,OSB and,untreated hemp mat skins.Tung oil provided resistance to tension failure and increased capacity to withstand considerable deformation without tensile failure in flexural specimens.Compared with pure foam specimens,untreated hemp mat improved flexural performance by 16.3%.展开更多
文摘The energy efficiency of a building depends on building envelope performance.The results presented in this paper are the first of a long-term building envelope research project at the Alternative Village at the University of Manitoba in Winnipeg,Manitoba,Canada.Five test buildings were constructed using the following systems:two wood frames with fiberglass batt insulation and dense pack cellulose,one polyurethane structural insulated panels(PUR SIP),and two with the Stay in place PVC concrete form building system using 102mm and 204mm of concrete externally insulated with 102mm of expanded polystyrene foam.All of the buildings had a common foundation and roof system with a footprint of 23.8 m2.Blower door tests were conducted to determine air tightness.Each structure was heated with an electrical resistance heater and maintained at a constant internal temperature.The thermal gradient through the wall and power consumption were monitored.The study period discussed in this report represents the main heating season from October 2011 to April 2012 consisting of 209 days.Based on the power consumption,the PUR SIP consumed the least at 2498 kWh,while the 204 mm Stay in place PVC concrete form building used the most at 2898 kWh for the same time period.The thermal gradient through the cross section of the wood frame structures was compared through the cavity insulation and at the stud.It was found that the cellulose building provided better thermal resistance along the stud when compared to the fiberglass batt insulation.
文摘The use of structural insulated panels(SIPs)for wall and roof assemblies in residential and commercial buildings is a well-known construction technique.SIPs typically use a combination of either expanded polystyrene foam(EPS)or polyurethane foam(PUR)as the core material.The covering or skin is predominantly oriented strand board(OSB).The OSB is either bonded to the foam with adhesive in the case of EPS,while polyurethane is used to provide adhesion with PUR SIPs.This paper presents the results of research that investigated the use of industrial hemp mat used as a skin for soy-based polyurethane foam panels.A series of tests were conducted to investigate moisture resistance and flexural behaviour on hemp mat foam panels.Moisture absorption behaviour was evaluated on three specimen types:uncoated,earth plaster and tung oil treated hemp mat.The absorption coefficient Aw was determined for all specimens.The tung oil treated specimens exhibited a water absorption coefficient that was 5.3%of that for untreated hemp mat panel specimens.Flexural tests were conducted on dry specimens with earth-plastered hemp mat,tung oil coated hemp mat,OSB and,untreated hemp mat skins.Tung oil provided resistance to tension failure and increased capacity to withstand considerable deformation without tensile failure in flexural specimens.Compared with pure foam specimens,untreated hemp mat improved flexural performance by 16.3%.