If you haven't had formal engineering training, understanding the construction specifications for a load-bearing masonry building can be difficult. This article provides definitions of several common but often confusing load-bearing terms: A-block f'm ASTM Grout Bearing wall Grout bond Bond Grout lift Bond beam Grout pour Box frame Grouting, low-lift Brick, clay Grouting, high-lift Cavity wall H-block Cleanout Lap splice Collar joint Lateral support Compressive strength Load-bearing concrete masonry Concentric load Load-bearing wall Cross-sectional area, gross Mortar Cross-sectional area, net Partially reinforced masonry Eccentric load Prism Effective "b" Psi Effective height Reinforced masonry Effective thickness Rodding Empirical design Shear wall Engineered (or rational) design Slenderness ratio