Slide 1In This Unit…Slide 3Slide 4Air leakage sitesWall AssemblyAir RetarderSlide 8Indoor air qualitySlide 10Slide 11Slide 12Fire PreventionFire safe constructionASTM TestCompartmentalizationTypes of ConstructionType II(B)Type V(B)Type IV Heavy Timber (HT)Firestopping penetrations, fire-sealing jointsInterior FinishesSlide 23Sound pressure (loudness) measured on decibel scaleAirborne sound falling on a building assemblyAirborne sound & building assemblySound transmission lossSlide 28Stud wall assembliesImpact Insulation Class (IIC) measure of structure-borne soundSound absorptionCeiling tilesPartitions: fabric-wrapped fiberglass panels absorb soundLecture 4: Properties of Materials IIKamalesh Panthi, Ph.D.Department of Construction ManagementEast Carolina UniversityCMGT 2210 - Construction & Civil MaterialsIn This Unit…Properties of MaterialsAir and Water Vapor Flow PropertiesFire Related PropertiesAcoustical PropertiesAir Leakage and Water Vapor ControlAir leakage - The leakage of conditioned air through cracks and unsealed joints in the building envelope.Factors that affect air leakageArea in envelope prone to leakageAir pressure differences between inside & outside airSolution: reduce air leakage areaAir leakage sitesWall AssemblyAir RetarderContinuous membrane applied to exterior of building enclosure prior to finish5-10 mil plastic sheetMicropores allow vapor to escape but retard passage of airApplied with staples, taped jointsAir retarder wrapped around exterior wood sheathing in wood light frame constructionIndoor air qualityA well-sealed enclosure can subject interior space to air pollutantsDust, pollen, micro-organismsCarbon dioxide, carbon monoxideVolatile organic compounds (from sprays, cleaning products)Formaldehyde (off-gassing from building products)Radon Interior spaces must be ventilated with adequate amounts of fresh air to prevent health problemsFire-Related Propertiesof MaterialsFire is the largest killer of building occupants in the United StatesFactors Affecting Fire SafetyArchitectural designConstruction materials and systemsFire detection and suppressionPublic educationFire PreventionBuilding CodeFire Prevention Code (NFPA in US) - safety in a building during use and occupancyLocating and maintaining fire protection appliancesMaintaining clear means of egressStorage of combustible materialsFire safe constructionRegulated by building codeCombustiblity of materials determined by ASTM testing requirementsNon-combustible materials will not add fuel to a fireASTM TestCompartmentalizationTypes of ConstructionType I & II noncombustibleType III & IV noncombustible/ combustibleType V combustibleType II(B)Type V(B)Type IV Heavy Timber (HT)Firestopping penetrations, fire-sealing jointsInterior FinishesFlame spread index (FSI)Measure of rate at which flames spread on the surface of an assembly.Determined by Steiner Tunnel TestScale starts with 0, no upper limitSmoke developed index (SDI)Measure of visibility through smoke developed from burning of interior finishesScale starts with 0, no upper limitAcoustical Properties of MaterialsSound pressure (loudness) measured on decibel scaleAirborne sound falling on a building assemblyAirborne sound & building assemblySound is reflected, absorbed & transmittedTransmission rate varies with weight of assemblyHeavy-weight assemblies are poor transmitters - good insulatorsLight-weight assemblies, poor insulatorsSound transmission lossImprove STC (Sound Transmission Class) of light weight assemblies byAdding fibrous insulation in stud cavitiesDecoupling gypsum board layerUse multiple gypsum board layersStud wall assembliesImpact Insulation Class (IIC)measure of structure-borne soundSound absorptionSound originating within room attenuated only through sound absorptionNoise reduction coefficient used to compare efficacy of materials (0-1)Higher NRC, the more sound absorptive the materialMaterials .2 NRC or higher are sound absorptiveCeiling tilesPartitions: fabric-wrapped fiberglass panels absorb