Breeze blocks are an alternative to bricks for constructing masonry footings and walls. Because they are made from a combination of Portland cement and the cinders from burnt coal, they are much lighter than bricks made from clay or concrete blocks made from cement and aggregate. Their light weight makes them easy to manoeuvre into position, and the mortar you use to hold them in place can be less firm than the mortar you would use for bricks or concrete blocks. Other than this, mixing breeze block mortar is similar to mixing mortar for bricks.
Pour a quantity of Portland cement or masonry cement into a 5-gallon bucket and transfer it to a mixing trough. If you don't completely fill the bucket, note the level of the cement in the bucket. If you are mixing a large batch and fill the bucket several times, note how many buckets you pour into the trough.
Measure out four times as much sand with the bucket and pour it into the trough if you are using Portland cement. If you are using masonry cement, measure out three times the amount of sand, and transfer it to the trough.
Mix the dry cement and sand together with a shovel or trowel.
Add water incrementally and work it into the mixture. You can regulate the amount of water you add more precisely if you pour it first into a 1-quart jar and transfer it to the mortar mix.
As the mixture becomes wet, test it periodically by transferring a little onto a metal plate and turning the plate over. It is ready to use when all of it adheres to the plate. If water drips from the plate, the mixture is too wet, so add more cement and sand in the correct proportions to firm it up.
Mortar mix remains workable for a limited time, so mix only the amount you can use in two hours. If you have to leave the mortar standing, cover it with a dust sheet or plastic sheet.
If the mortar is too wet, it will run around the edges of the blocks and allow them to settle, creating an uneven structure. If it is too dry, it won't adhere properly, and the structure may not be stable.