Dictionary of Moisture Protection & Restoration

Masonry = Art and craft of laying masonry units of brick, concrete block, glass block, structural tile, and stone. Also construction of units of such materials as clay, shale, concrete, glass, gypsum, or stone, set in mortar. The following are different types of masonry: 1. Hollow masonry- units in which the voids exceed 25% of the cross-sectional area; 2. Solid masonry-units in which the voids do not exceed 25% of the cross- sectional area at any plane parallel to the bearing surface; and 3. Modular masonry-units manufactured to a nominal four-inch module size or a multiple of four inches. Mortar = Plastic mixture of cementitious materials, sand (aggregate) and water; used as a bed and for cementing masonry units in place. Also called mud. Mortar types: Type S =

1 part Portland Cement 1/2 part Hydrated Lime 4 1/2 parts sand or 1 part Type II masonry cement 4 1/2 parts sand

Type M =

1 part Portland Cement 1/4 part Hydrated Lime 3 parts of sand or 1 part Type II Cement 6 parts sand

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