FROM BOTTOM TO TOP: LAYING THE FIRST COURSE Using a brush, clean the block surface before installation. Lay the first course over a semi-dry cement-sand mortar levelling bed. Corner blocks are laid first and the first course should be completed before the second course installation. Once the corner blocks are placed, use a brush to clean the next block surface before mortar application. Ensure that the top level of all blocks is at the same height. This can be checked with either a straight rod or a simple level-o-meter. Any undulation might lead to uneven load and result in cracks.

BEGINNING WITH CORNERS Set the first corner block in the sand-cement mortar and adjust the joint as needed. To achieve the required height, lower or raise the block by tapping down with a rubber mallet. For the next block, apply mortar to the vertical joints using an appropriate notched trowel. The trowel should be as wide as the block. After installing each unit, plumb and level should be checked immediately with mason’s level. Corners are to be made in an alternate fashion, so that both walls fit into each other.

TOP LEVEL The space between the upper beam/ top plate and bottom block just below it is to be filled with smaller blocks to adjust the building height.

LEVEL The level from the base to the top layer should be properly horizontal. There should not be any gaps between the joints.

FASTENERS Anchors used with AAC shall be made of plastic or nylon. Wood, fiber, lead, metal or expansion anchors are not recommended. To make holes for the fasteners, power drills are used. The anchor should pierce tightly in the hole to avoid rotation when placing the screw.