Thermal Barriers
ICF units exposed to the building interior must be finished with an approved 15-minute thermal barrier.
Such as minimum ½ inch thick (12.7 mm) regular gypsum wallboard complying with ASTM C1396, installed vertically and attached to the cross-tie flanges with minimum 1-5/8 inch long (41 mm), No. 6, Type W, coarse-thread gypsum wallboard screws spaced 16 inches (406 mm) on center vertically and 12 inches (305 mm) on center horizontally.
The screws must penetrate a minimum of 1/4 inch through the flange. Gypsum board joints and screw heads must be taped and finished with joint compound in accordance with ASTM C840 or GA216.
Other approved finishes such as BuildCrete may also be used.
Reference the BuildBlock Code Compliance Research Report (CCRR-1003) for additional specifications and information.
