The surfaces on which the block work has to be done shall be sound and confirm to good design, rigid, clean and free of dirt, oil, grease, curing compounds, form release agents or loose plaster and paint For economy the surfaces should be level and true within : Floors – 1.5mm in 1.0m
- If a plaster/leveling mortar bed is applied, ensure that it is cured for at least 7 days to achieve proper strength before application of adhesive for construction of block work
- Ensure the substrate is clean and free from impurities like dust, dirt, debris, oil, grease, curing agents, existing paints, loose plaster etc.
- Dampen the surface before application of adhesive
- Clean the back of block for any dust or coating
The product can be mixed by hand or slow speed electric drill mixer (less than 300 rpm). Pour water in a clean container and then add the powder BLOCK FIX adhesive until the mixture becomes creamy and plastic. Do Not Overmix. Leave the mix to slake for 5-10 min and remix before use. Mix only sufficient quantity of adhesive for immediate need. Proportion: Approximately 1 bag of 50 Kg of BLOCK FIX Adhesive with 12 to 15 ltrs of Water. Adjust quantity of liquid to obtain proper consistency.
Wet the surface and remove the excess water before applying the adhesive. Ensure the area is shaded from sunlight. The adhesive shall be applied with the flat side of the trowel using a scraping motion to work the material into good contact with the surface to be covered. Additional mortar is then applied with the notched edge of the trowel.
- Thin bed mortar for laying blocks: Before placing mortar, ensure the block work to be dry and surfaces cleaned properly. Place the mixed mortar on the block work in thin layers of 2 to 3 mm (or as required by engineers at site) using trowel and place the next layer of blocks on the mortar. Keep joints between the blocks as required by the site engineers and fill the joints with the mixed mortar, using a trowel. Check the plumb of the wall while laying the blocks to keep the walls perfectly vertical to the plumb.
- Smoothing over the block work: Before placing mixed mortar, apply a bonding layer of 1 to 2mm thick AAC Block Adhesive mortar using a trowel pressing down on the block work. Then apply AAC Block Adhesive at a thickness of 8 to 10mm and smoothen using a sponge or rubber / wooden float. When installing large blocks, spread higher thickness of AAC Block adhesive. Select proper type of notched trowel.
a) Large Blocks up to size 600 X 240 mm X 100 mm use a square notched trowel of size 12mm X 12mm to provide a total thickness of 6mm
b) Medium blocks up to size 400 X 150 mm X 100 mm, use a square notched trowel of size 6mm X 6mm and back butter the block with the same adhesive to a thickness of 1-1.5mm to provide a total thickness of 4.5mm
c) Small blocks up to 200 X 150 mm X 100 mm, use a V notched trowel of size 3mm X 3 mm and to provide a thickness of 1.5mm to 2 mm.
- As Adhesive to install tiles: AAC Block Adhesive can be used as a thin-set adhesive to install tiles on AAC Block/Fly ash brick walls. Use a suitable notch trowel to achieve desired thickness of adhesive for installation of tiles on the wall.
- The most important standard to keep in mind is to ensure that the piece of block is completely bedded in the mortar or adhesive with 100% coverage after Beat in.
- Excess mortar on adhesive shall be cleaned from the surface of the blocks with wet cloth or sponge while the mortar is fresh.
Expansion and Control Joints
All slabs must be plumb and true to within ¼” (6mm) in 10 ft (3m). Follow ANSI Specification AN-3.8 “Requirements for Expansion Joints” or TCA Detail EJ171 “Expansion Joints”. Do not cover expansion joints with mortar.
- Existing joints in concrete must be carried through tile work and shall confirm to architectural details
- Interior installations shall have movement joint spaced a maximum of 10m X 10m. For exterior areas it shall be spaced at 5m X 5m and shall confirm to architectural details
Areas of Application
For interior and exterior use for preparing thin bed block mortar for ALC and cellular concrete blocks
- Concrete blocks
- Cement mortar blocks/bricks
- Concrete hollow blocks
- Aerated light weight blocks
- Cellular concrete blocks
- Fly ash bricks