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FGIA, NGA revamp capillary tube guide for insulating glass units

The Fenestration and Glazing Industry Alliance (FGIA) and National Glass Association (NGA) published NGA/FGIA TB-1601, Guidelines for Use of Capillary Tubes.
The Fenestration and Glazing Industry Alliance (FGIA) and National Glass Association (NGA) published NGA/FGIA TB-1601, Guidelines for Use of Capillary Tubes. Photo courtesy Fenestration and Glazing Industry Alliance (FGIA)

The Fenestration and Glazing Industry Alliance (FGIA) and National Glass Association (NGA) announced a joint publication of an updated technical resource, NGA/FGIA TB-1601, Guidelines for Use of Capillary Tubes.

The eight-page guide addresses the use of capillary tubes in insulating glass units including proper manufacture and design, glazing methodologies, as well as advantages and disadvantages of their use.

“This is an excellent resource covering the use of capillary tubes; everything from design guidance to glazing considerations,” says Aaron Thompson, principal research engineer at Viracon Inc., based in Owatonna, Minn. “The volunteers comprising the task group have worked over the past two years to bring the material up to date and in line with expanded knowledge and use since its original publication in 2014.”

The resource further expands on environmental conditions, discussing how gas fill, temperature and pressure impact IGU behavior.

“The use of capillary tubes in insulating glass units (IGUs) has long been established as a means to accommodate changes in elevation of an IGU from the point of IGU manufacture to the point of installation,” says Amy Becker, FGIA’s glass products specialist. “Such elevation changes create pressure differentials between the IGU cavity and the exterior environment that, unless alleviated, can cause glass deflection, excessive edge seal stress, and/or glass breakage.”

To download NGA/FGIA TB-1601, Guidelines for Use of Capillary Tubes, visit FGIA’s website.