Posted by JOHN LOZAover 4 years ago
Char clearance at face of HSS beam
How much clearance should we allow for char expansion of intumescent paint alongside of a HSS beam to allow for installation of exterior grade cold formed framing used to support exterior sheathing. In the past we were informed the intum paint will not expand until after any construction covering it would have already fallen off. Is this correct to assume?
1 Reply
Posted by Perla Salcedoover 4 years ago
Hello John, we typically see intumescent expand about two inches in fire scenarios, therefore we ask for a two-inch clearance. The intumescent will only activate/char/grow if there is fire present.
Perla V. Salcedo, MS
Steel Protection Engineer
Hilti North America
E: perla.salcedo@hilti.com
W: www.us.hilti.com