1- The block should be unloaded using appropriate equipment such as a forklift.

If pallets are worn or collide with each other, there is a possibility of damaging the corners of the block. If unloading is done on the roof, it should be distributed at a level close to columns and shear walls. The adhesive storage, similar to cement, should be placed on a dry floor with a minimum distance of 10 centimeters from the ground and should not be exposed to rain.

2- Block adhesive should be used for laying the blocks.

The block adhesive should be mixed in a suitable plastic container with clean water.

If the air temperature is less than 5 degrees Celsius, warm water should be used. Mixing should be done until a uniform mixture (honey-like) is obtained. The mixture should be stirred again before use, and the usable time for the prepared mixture is about one hour.

Under the work (the place for laying the wall blocks), a smooth and level surface should be created with a thickness of 1 to 2.5 centimeters using a sand-cement mortar (with a mixing ratio of one part cement, one part hydrated lime, and six parts sand). In ground floor walls (at a distance of less than 30 centimeters from the ground level), a layer of waterproof insulation should be applied before executing the mortar. Blocks must be soaked in a large container during installation to prevent excessive water absorption of the mortar during installation.

3- The first course should be executed with precise control of level and alignment.

First, the main extensions and then the intersections should be worked on. After installing each block, its surface should be cleaned, and then block adhesive should be applied to the vertical surfaces. The minimum thickness of the adhesive is 2 millimeters and the maximum is 3 millimeters.

A trowel or spatula should be used for applying the adhesive.

After installing each block, its level and plumb should be checked. Corrections should be made within less than 5 minutes with gentle taps of a rubber hammer.

It is better for the outer surface of the block to be a few centimeters ahead of the metal columns and insulated on the columns. This is to prevent thermal bridging at the location of metal members.

To prevent the effect of infill during an earthquake, it is better for the walls to be executed with a distance of one centimeter from the columns, beams, and concrete walls, and connected to the structure with metal straps at a maximum distance of two blocks. For filling the gaps, special mortar adhesive or dead plaster can be used.

4- Cutting can be done with a hand saw, band saw, and carpentry tools to the desired dimensions and shapes.

5- Drilling should be done with a rotary cutting machine.

The diameter of the hole should not exceed one-third of the depth of the block. The edges of larger holes should be reinforced with metal mesh.

6- Execution joints at horizontal distances

Should be considered 10 to 13 millimeters for a height of 3 times the wall height or 6 meters. Connection straps should be used at a maximum of every 2 courses of blocks. For executing a non-dry stone facade that has a smooth surface with dimensions larger than 6 meters, vertical and horizontal expansion joints of one centimeter thickness should be executed every 6 meters.

7- It is emphasized again that during execution, the surface of the blocks should be moist.

For the installation of subsequent blocks, vertical and horizontal surfaces should be applied with adhesive using a trowel. The surfaces of the blocks should be cleaned before applying adhesive. During the installation of the block, sliding the block should be avoided, and excess mortar should be cleaned with a spatula. The overlap of the blocks should be at least 15 centimeters (the minimum distance for vertical joints is 15 centimeters) and should be consistent for each course. In the intersection of angled walls, vertical joints should not overlap. To ensure the wall is plumb, the level and alignment of each block should be checked after installation. Use perforated metal connections (straps) at the junctions of auxiliary walls, joints, and connections to columns.

If the walls at the junction are of the same thickness, they should be laid simultaneously.

The auxiliary wall, which is thinner than the main wall, should be connected to the main wall with an execution gap of about 1 centimeter and using steel strips spaced one meter apart. The connection of auxiliary walls in L or T shapes that are of the same thickness should be executed in a staggered manner. To connect the wall to concrete columns, a perforated metal piece that is connected with screws to the wall and to the column with welding or screws can be used.

To connect the wall to metal columns, a perforated metal piece that is connected on one side with screws to the wall blocks and on the other side to the column with welding or screws can be used.

8- If the height of the wall is more than 3.5 meters

Horizontal ties connected to the building frame should be used. If the length of the wall exceeds six meters or 40 times the thickness of the wall, vertical braces or ties connected to the building frame should be used. The vertical and horizontal edges of the partitions should be free.

9- Installation of utilities and patching the wall surface

For utility pathways, vertical grooves and drilling can be executed in the walls. After the utilities, to repair chips and patching, special adhesive can be used.

10- It is recommended that doors and windows not be installed directly on AAC blocks.

Suitable wall posts should be used to secure them. The metal frames of the doors should be filled with sand-cement mortar or special mortar adhesive.

11- Considering the smooth surface, the finish can be selected.

The wall can be finished with wallpaper, thin layers of plaster, ceramics, patterned acrylic coatings, or ready-mixed mortar. Before executing thin plastering and non-dry facades, the surface of the block should be thoroughly cleaned and then moistened. At the junction of different materials in the facade (such as the junction of AAC blocks with reinforced concrete shear walls or metal concrete frames), rabbit mesh (with horizontal strap direction) should be used.

Summary:

Observing the following items indicates correct execution:

– The best time for wall laying is after the completion of the ceiling concrete pouring operations. It is better that the ceiling concrete has gained its 6-day strength before wall laying.

– Wall laying is prohibited at temperatures below 5 or above 40 degrees Celsius, unless approved by the supervising authority and considering necessary measures.

– Keeping the blocks moist during execution should be observed to prevent water absorption of the mortar and ensure that the blocks are firmly set at the junction.

– Use of perforated metal connections at the junctions of auxiliary walls, joints, and connections to columns.

– Walls should be plumb.

– Grooving the wall for utilities should be done with a grooving machine.

– Vertical joints of the blocks in two consecutive rows should not be aligned.

– The staggering of walls at the junction of two walls should be observed.

– At the junction of the wall to columns or shear walls, suitable brackets should be installed.

– If the length of the wall is long, suitable wall posts should be considered for it.

– Suitable wall posts should be executed around the windows.

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