Metal Construction News, February 2021

Allowing easy one pass insulation installation for a secure long term connection By Bill Lippy Gain Thermal Performance on Retrofits with Fasteners Thermal bridging is a weak spot in energy efficiency and a challenge for designers and contractors across the industry especially for those in the metal building market Because steel serves as an excellent conductor and conduit for heat transfer metal building erectors and contractors often seek the best solutions to reduce thermal bridging to create more energy efficient comfortable buildings What is commonly known as metal building insulation MBI which is typically constructed of various amounts of fiberglass with a laminated facing and attached with a banding system has been used widely for decades and can usually provide enough R value to meet strict codes However this system may not be the most effective way to also reduce thermal bridging and to reduce heat transfer that occurs at exposed metal purlins struts and beams By reducing the thermal bridging throughout the building many owners can save a considerable amount in utility bills Weigh Options for High R Requirements Finding versatile more comprehensive solutions for high R requirements is easier today than it was 20 years ago For example when the code requires R 30 depending on the condition and R value of existing insulation contractors can select a fiberglass MBI to gain an additional R 11 R 13 or R 19 in retrofitting the building Another good retrofit option for higher R requirements is a reflective double bubble insulation Reflective bubble insulation enhances air gaps in enclosed cavities of the ceiling or wall systems It works when a low E aluminum surface faces an enclosed air space Commonly used for bar joist or purlin applications this option can gain as much as an R 65 and can reduce the thermal bridging for better overall performance Yet another option is double bubble insulation attached on the bottom of purlins to enclose 6 to 8 inches of air space This application provides superior performance with as much as R 16 when both sides have a reflective surface facing the cavity and the inside of the building or an R 12 when the reflective side is facing the cavity and the other white side offers a clean finished ceiling and a brighter workspace Both examples represent a heat flow down summertime application where reflective insulation outperforms other airbased insulation products such as fiberglass Still another option is a hybrid system of reinforced reflective doublebubble insulation backloaded with blown fiberglass to gain much higher R values These systems when attached with snap on mechanical fasteners are strong enough to support a variety of hybrid solutions Attachment Methods In new construction most MBI is often attached with a banding system that requires a three pass installation process to get it secured properly Years later when it comes time to re insulate contractors commonly will choose components known as stick pins which involve cutting into existing insulation in order to glue the pin plates in place on the steel framing behind the insulation Then once the glue dries the crew returns at least a day later to install MBI on the pins But many times as known widely in the industry the glue fails to hold the stick pins and failures occur Mechanical fasteners are a viable alternative which contractors have been using now for over two decades as part of an insulation system The proven mechanical fastener systems are now sold separately designed to work with all types of metal framing and can be easily secured to a variety of insulation and facings Mechanical fasteners clip pin attach directly to bar joist beams or purlins which allow a quick and easy one pass installation for a strong secure long term connection Contractors can use the fasteners with all types of insulation including MBI facings and reflective bubble Correctly installed the clip pin fastener system is strong enough to securely hold more than 60 pounds of mass insulation Metal building insulation systems installed with mechanical fasteners can significantly reduce labor costs and operational downtime and provide the owner with long term performance Bill Lippy is president and CEO of Fi Foil Co Inc Auburndale Fla vice president of the Reflective Insulation Manufacturers Association RIMA International co chair of the Code and chair of the Strategic Alliance Committees Lippy is a longtime building science advocate For more information on reflective technologies and mechanical fastener systems visit www fifoil com fastenersystems or call 800 448 3401 February 2021 METAL CONSTRUCTION NEWS 27 www metalconstruct ionnews com