Franklin Stone

Architectural Masonry / Franklin Stone

Franklin Stone Fire Ratings

Fire resistance ratings are calculated by the percent of solid material in the concrete masonry unit by the actual thickness (in inches) of the units to determine the hourly rating for the type of aggregate used. All Franklin Stone units are 100% solid and are of a limestone material.

FIRE RESISTANCE RATINGS/MINIMUM REQUIRED EQUIVALENT INCHES

Aggregate Type Fire Resistance
0.5 Hr. 0.75 Hr. 1 Hr. 1.5 Hr. 2 Hr. 3 Hr. 4 Hr.
Limestone 1.9 in. 2.3 in. 2.7 in. 3.4 in. 4.0 in. 5.0 in. 5.9 in.

EQUIVALENT THICKNESS OF FRANKLIN STONE (IN INCHES)

Nominal Width
(Inches)
Equivalent Thickness
(100% solid)
Fire Resistance
4 3.625 in. 1.5Â Hr
6 5.625 in. 3.0Â Hr
8 7.625 in. 4.0Â Hr

(1) Information based on data published by the National Concrete Masonry Association in NCMA TEK 7-1A, available from Northfield.