All aggregates shall be a rotary kiln expanded shale lightweight aggregate. It shall be NORLITE or equal as approved by architect and conform with ASTM Designation: C 331 "Lightweight Aggregate for Concrete Masonry Units". The term Norlite applies to lightweight aggregates produced by the Norlite Corporation, Cohoes, New York. The weight of Norlite concrete from which the masonry units are made shall not exceed 105 lb. per cu. ft. when measured in accordance with provisions of ASTM Designations: C 140 "Sampling and Testing Concrete Masonry Units".
All concrete masonry units shall conform with the following ASTM Designations:
- C 55 Standard Specification for Concrete Brick
- C 90 Standard Specification for Load Bearing Concrete Masonry Units
- C 129 Standard Specification for Non Load Bearing Concrete Masonry Units
Masonry units shall be stacked on planks off the ground, and in wet weather shall be covered to keep dry. Mortar shall comply with ASTM Designation: C 270 Standard Specification for Mortar for Unit Masonry either Property Specifications or Proportion Specifications except that type O and K mortars shall not be permitted.