b'ar concrete roof decksinImem degradation.CellularDimensionalStability-Itwoulddays until themembrane is ight ofbraneroofing these criteria.concrete withits discrete cell sys be dimensionally stable under vary applied. Compatibility with Bitu andtemdoesnotbecomesofta ing temperature and moisture con Undernormalconditions,the mennd Other Adhesives-It would be able tomushy ifto water as doesditions.roofingmembraneoverallular exposedcewithstandtheeffectsofbeinginsome rig insulation board.Monolithic cellular concrete andcon roof deck may be installed idcrete contactwithadhesives,solvents,ThermalResistance-Itwouldsandwiched E insulationrd is3-5 days after the deckis cast.If PSboaand hot bitumen at the applicationhave aconductivity (k a dimensionally stablesysteminthere is rain during the firstdays low thermalfew temperatures required for installa value) so that the highest possiblethe presence of varying temperatureaftercasting,the watertypically tion of the roof membrane.thermal resistance (R-value) can beandmoistureconditions.Rigidflowstothedrain.If thedeckis Cellularconcreteisaninertachievedinthethinnestpossibleinsulationboardsystemshaveexposedlo rof time, fornge periods materialthatprotectsthesand piece of material.joints thatopen under chang drying shrinkage cracks may appmayear wichedexpandedpolystyreneEPSinsulationboardissand ing environmental conditions.and permit water toenter the roof (EPS) insulation board from adhe wiched w the cellular concreteComponent Capability-Itwoulddeck system. Sometimes water may ithin sives,solvents, andhotbitumenroof deck and provides most of thebe formulated lo be compatible withpenetrate the deck at verticaluprotrwith a2" thick cover.insulation for the roofsystem.theother components of theroofsions (which h not been flashminimumdeckaveed) Impact Resistance-It would haveThecellularconcreteactsasanassembly.or at drains (whichnot be commay strength, rigidity,ahighinsulationprotection as wellas aInsulating cellular concrete roofplet . anddensityed)enough to resist impactheat sink to moderatemem decksystemsarecast-in-placeThe 3 day membrane installadamage.deck-5 densi to roCellular concrete, with atybrane temperatures.Thisreducessuchthat roofdeckpenetrationstion timeframe appliesof decks of 30 pct, is stronger than insulationthermal shock to the roofing mem and mechanical equipment barrierswith mechanically attached (nailed) board andresists impact damagebrane that may occur with high R that occur on every deck can be eas baseover which aor sheetsbuilt-up during construction and the servicevaluerigidinsulationboardily accommodated. P slop modifiedbitu roofing memositivee men lifeof themembrane. This differ systems.to-d rainiscreatedduringbraneisappliedandforfully ence between cellular concrete andStablek-Value-Thek installation along with the casting ofadhered,fleece-backedsystems -value rigidinsulationboardisreadilywouldremain constant and wouldmonolithic saddles andcantsthatWhen using fully,thadhered smootpparent from just walking on thesenot drift with age (i.e., the insulationdirect the water toward the drains assurfacedmembranes,a test patchdecks.wouldnotlose thermalresistancedesigned.m be required to assure that the ay Fire Resistance-It would be non over time).deck is ready to be roofed using the combustible andwouldcomplyBoth cellular concrete and pro Wind Uplift Resistam:especified adhesive. with the requirements of insurancetectedEPSinsulationboardhaveThe monolithic nature of cellularCellularconcrete,usuallycast underwriters a building codes.stable k-values. Depending on theconcrete roof decks block air move 2" thick over the EPS board, hnd-3"as Cellular concrete provides atype of material,rigid insula ment from inside the building dur such a low water content that most Fac some and ULdrift plift tory Mutual Class IClass Ation board roof systems have aingwindu conditions.Asaof thiswater is consumedby the FireRatingwithover 50 systemsing k-value over time.result, air barriers are n needed ashydr ion of the cement and/or disotatlistedintheULFireResistanceAttachmentCapability-Its sur p of a roofingsystem forhighsipates fromexposuresun and artto Directory. Furthermore, since cellu faceswould accommodatesecurewind uplift ratings.wind. After amoisture few days, the lar concrete fills the flutes on steelattachment. Also,its resistance tocontent of the cellular concreteis decksystems,fireproofingthemoistureabsorptionwouldnotSpecial Installationsuitable for roof membrane installaunderside of the steel decking is notimpair itsphysicalpropertiesandRequirements for Cellulartion. necessary.Rigidinsulationboardattachment capabilities.Concrete Roof DecksDavid Siple,his articlerin"Pouroof decks require underside fire The base sheet of mechanically Althoughcellular concreteroofingCellularConcrete OverNonproofing of the steel deck for manyattachedroofingmembranesisdecks meet all the criteria of an idealVenting Substratest Don\'t Get (Bubuilding code classifications.nailed dir into the cellular con roofinsulation,theinstallationCaught in theRain),"offers some ectly MoistureResistance-Itwouldcrete with the built-up or modifiedprocessmayhaveonedisadvan very practical advice for insula ng tiresist the effects of moisture vaporbitumenmembranesappliedinatage, in the view of som relative tocellularconcrete r decksthat e,oof and free water without degradationnormal fashion to this base sheet.a rigid insulation board system.may be exposed to rain: over the life of the building.Fully-adheredsystemsmaybeDue to the fact that an insulatingS fytheroofdesignto impliCellular concrete roof decks pro installed adays after the cellularconcreteroofdeckis a cast-in reduce deck casting and roofing few vide positive slope-to-drain that isconcrete deck is cast. These decksplace cementitious product, it can application times. cast-in-placeduringconstruction.donothave thenumerous jointsnotberoofedthesamedayit is Conti on page 12 ll.s awater will not pond onthatoccur withrigidinsulationinstalled. As a result,thedeck isnued result, ne decktobecomea sourceofboard systems.exposed toelements for several the'