The ability to produce load-bearing masonry units adopting ACI 211.1 mix design using (1:3.2:2.5) as (cement: fine aggregate: coarse aggregate) with slump range (25-50mm) which can conform (dimension, absorption, and compressive strength) within IQS 1077/1987 requirements type A was our main goal of the study. The ability to use low cement content (300 kg/m3) to handle our market price products since the most consumption in wall construction for low-cost buildings was encouraging. The use of (10 and 20%) of LECA as partial volume replacement of coarse aggregate to reduce the huge weight of masonry blocks can also be recommended. The types of production of the load-bearing masonry units were A and B for (10 and 20%), respectively. Finally, the use of the spray curing method was the more suitable simulation of reality and easier for factory producers, taking into consideration that the increasing curing time from 14 days (recommended in IQS 1077/1987) to 28 days may be led to conversation masonry type from B to A as in R20%-300.
