Smoke Control in High-Rise Buildings - FCIA - Firestop Contractors ...

ASTM E2307 test method and the fire load as requiredin the standard.Industry awareness is critical of these findings,especially with literature reviews on glass breakage,heat flux energy created when the flame extends abovethe floor due to spandrels shorter than 36 inches, andfull height vision glass. Although limited testing hasbeen done with short spandrels along with varyingresults, the recent findings indicate that with life safetyas the primary concern, thought needs to be given towhat would occur should an uncontrolled fire develop.Types of Curtain Wall AnchorsAnchors used to hang a unitized curtain wall on theexterior of a building are typically made of aluminum.Recently, designs and installations have the anchorsmounted to the underside of the floor slab with directexposure to flame and hot gasses should a fire occur.Specifications need to address the protection of theseanchors in that event. Aluminum not only melts intypical fire temperatures, but loses structural strengththereby subjecting the unitized curtain wall to shiftand potentially cause failure at the perimeter joint.Flame and hot gases would then enter the floor above.This creates the domino effect that the perimeter fireprotection was installed to prevent.Nature of the curtain wall components (e.g.aluminum framing, extrusion design, spandrelpanel design, wet or dry mullions and transoms)along with the floor rating and structural designsoften impedes efficient and proper installation.Floor-to-ceiling glass means a transom will belocated at the slab. Transoms and the extrusiondesigns that are located at floor level often prevent anaccessible means to mechanically attach the spandrelinsulation and mullion covers, or provide the spacenecessary to install a standard backer bar for supportingthe safing insulation at the perimeter void. A recenttested and listed system published in the UL FireResistance Directory (CW-D-1012) helps resolve thebacker bar issue and congestion that occurs at the edgeof slab and the curtain wall mounting anchor.Issues with transoms extruded with special shapesintroduce another element on how to mechanicallyattach the spandrel insulation when standard hangerswill not work. Custom hangers are one alternative.Mullions and transoms designed to channel wateraccumulation away from the building and maintaina dry structure means minimum or no penetrations.Any permitted penetrations must be sealed to preventwater leakage over the life of the building. Structuralfloor designs that prohibit the installation of mullioncovers can be resolved by installing safing at the top andbottom of the beam and still providing the smoke stopseal at the top of the slab.Building geometry at curtain wall – inclined,staggered, curved, etc.Unusual and unique building designs are increasingwith today’s technology. A building’s curtain wall thatis designed and installed with various angles and shapescreates an exposure that in event of a fire will cause theglazing to break and fall out. Again, the result is flamesand hot gases spreading to the floor above bypassing theperimeter fire containment system.Thinking Toward the FutureProfessional Training YieldsExpert FireproofersFire Rated Walls A Great Finished Deck Applying the Proper ThicknessCall us for information about today’sfireproofing and plastering systems andthe best people to apply them.Chicago Plastering Institute5611 W. 120th StreetAlsip, IL 60803(708) 371-310018 life safety digest /// Fall 2012