Laying First Row of AAC

Content under development. March 2008.

When you lay the first row of Autoclaved Aerated Concrete (AAC) you use a standard mortar, roughly 3/8 of an inch thick. This is refered to as the leveling bed mortar. It helps compensate for slight uneven variations in the concrete slab. It is important to match the strength of mortar to the strength of the block. Thus the mortar used for concrete masonary units (CMU) has a different ratio of cement, lime and sand than the mortar used for clay bricks or AAC. Additives may need to be added when the temperature is above XX degrees or below XX degrees.

The leveling bed mortar for AAC should consist of XX parts of sand, XX parts of portland cement, XX parts of lime, and XX parts of water.

First two blocks layed String lines help immensely in squaring up the inside edges of the exterior walls.

Laying AAC on frost wall:

If the top of the frost wall is above the garage floor, follow the next four pictures for laying the first row .

Frost walls for garage Start with corner blocks and work towards center.
Spread leveling bed mortar Trowel on leveling bed mortar.
Batter end of previous block with thinset mortar Apply thinset mortar to end of previous block.
Set block and check elevation with builder's level (or transit). Check elevation with a builders level and/or string line.