Thermal and Moisture ProtectionMajor TopicsMajor Topics con’tSlide 4Moisture ControlKey Moisture Absorption ConsiderationsPermeabilityMoisture CondensationWaterproofingMembraneSheet MembranesBituminousClay waterproofingCementitious WaterproofingDampproofingBuilding InsulationRigid InsulationMineral Fiber InsulationLoose-fill InsulationFoamed-in-place InsulationRoofingExamples of Single-Ply MembranesExample of Built-up RoofSteep RoofingRoofing Material and SlopeRoofing UnderlaymentUnderlayment Performs These Functions:Types of Roofing MaterialsRoofing StylesExamplesSlide 31Examples of RoofingComparison of Types of RoofingFlashingTypical Locations for FlashingSidingSealantsReferences1Thermal and Moisture Protection2Major TopicsMoisture ControlWaterproofingMembraneClayCementitiousDampproofingHot-appliedCold-applied3Major Topics con’tBuilding InsulationRigidMineral FiberLoose-fillFoamed-in-placeRoofingLow vs. steep slopeTypes of roofing materials4Major Topics con’tFlashingSidingSealants5Moisture ControlMoisture is NOT damaging to construction in its vapor form…the problems arise as itCondenses (liquefies)Freezes (solidifies)These may cause organic materials to decay, metals to corrode, paint coatings to blister, and in the case of freezing, may cause concrete and masonry to crack.6Key Moisture Absorption ConsiderationsDimensional instability – the changes in moisture can cause a change in material dimensions (ex: wood drying)Deterioration – causes physical, chemical, and biological breakdown of materials (ex: steel rusting)Condensation tolerance – varies for each materialEffect on heat flow – if material contains moisture it can increase the conductivity7PermeabilityPermeance – measure of water vapor’s flow through a material of specific thickness or an assembly of several materialsMetals & glass – very low permeabilityMaterials with a permeance of 0-1 are considered vapor retarders See Figure 7.1-7 on page 431 for examples of various materials and their permeance8Moisture CondensationMoisture condensation in walls, floors, and roof and ceiling assemblies can be controlled by:Providing a vapor retarder on the interior side of the assembly which limits vapor entering the structureProvide adequate ventilation for the structure in spaces such as attic areas and crawl spaces9WaterproofingAs defined in ASTM D1079: “the treatment of a surface or a structure to prevent the passage of water under hydrostatic pressure.”10MembraneFluid-applied membranes are usually:PolyurethaneHot Rubberized Asphalt – not as elastic as polyurethane and requires a thicker coat11Sheet MembranesButyl synthetic rubber sheet [60 mils thick]Ethylene propylene diene monomers (EPDM) [min. 1/16” thick]Pre-molded bituminous [7 ply]Rubberized asphalt [56 mils]Self-adhesive butyl [60 mils- requires adhesive primer]12BituminousUsually applied on vertical below-grade surfacesHot coal-tar pitch or hot asphaltThe number of plies, overall thickness, and content vary according to the depth of the hydrostatic head (in ft. – all increase as the depth increases)13Clay waterproofingBentonite clay – when wet, it expands to between 10 to 15 times its dry volume.It is typically mixed with water & sprayed in place (also available in dry sheets between cardboard)Placed below grade to exterior surfaces14Cementitious WaterproofingComposed of portland cement, aggregate, and an acrylic or plastic admix. It may also contain iron fillers (then known as iron oxide waterproofing)Hydraulic cement – another form of cementitious waterproofing used to seal holes, cracks and open joints (often in free-flowing water)15DampproofingMay be hot- or cold- appliedHot consists of an asphalt primer or a coal-tar-based primerUsed on the exterior of buildings- not interior because of lingering odor and the problems associated with using “hot” products indoors.16Building InsulationUsually added to the roof, walls, and floors of a structure4 basic classifications are:Rigid boardMineral fiberLoose fillFoamed-in-placeListed according to their R-Values17Rigid InsulationUsable in all parts of a building –usually in a board formMost are [Resistance/inch]:Polystyrene – sensitive to daylight, give off carbon monoxide while burningPolyurethane [6.25] – may expand after exposure to moisturePolyisocyanurate [7.2]Perlite [2.78] – will not burn, tends to absorb waterPhenolic [8.3] –breaks easily, corrodes metalCellular glass block- [2.5] – breaks easily, deteriorates if exposed to freezing & thawingOrganic fiber – roofing systems primary use, wood fibers and water resistant bindersGlass fiberComposites – take advantage of high R-values of some materials in combination with the stability of others18Mineral Fiber InsulationProducts made from fibers from rock, slag, or glassNaturally resistant to fire, moisture, and verminMay be semi-rigid boards, batts, or blankets (longer than batts and sold in large rolls). Intended to fit between studs (16” or 24” o.c.)19Loose-fill Insulation Comprised of fibers, granules, or chipsMay be poured or “blown” into attics or wall cavitiesCommon additives may include: adhesives, and chemical treatments to resist fire and vermin20Foamed-in-place InsulationCreated by a chemical reaction that expands a mixture of components as much as 30 timesCuring typically takes from 24-72 hours, at which time the mixture solidifies into a cellular plasticCare must be taken not to “overfill” a cavity21Roofing Low slope – in general, these are roofs which slope less than 41/2”/ft.On low slope roofs a system of compatible components is selected to work together to form a waterproof membraneCommon systems used are: built-up roof or single-ply22Examples of Single-Ply MembranesEPDM – [ethylene propylene diene monomer] factory cured elastomer, bonded to themselves using adhesivesCSPE (DuPont Hypalon) –synthetic rubber, may also be liquidCPE – un-reinforced or polyester reinforced sheet materialPIB – formulated from isobutylene and other polymers, carbon black, and additional additives23Example of Built-up Roof24Steep RoofingSlopes exceed 41/2”/ft.Many materials used in modern roofing practices existed centuries ago