If you are doing some do-it-yourself work with concrete blocks, that may require you to mix your own mortar. While it may sound simple, it can be much more difficult than you can imagine. Mortar that is mixed incorrectly may not hold the blocks in place. It could crack, break or cause the constructed item to be unsteady and insecure. For safety reasons, as well as for the overall look, it is important that the mortar be mixed the proper way.
Preparing for the Process
Check to see if there are local masonry requirements. These will need to be followed with 100 percent accuracy.
Apply for the appropriate permits for the block structure being built.
Determine how much mortar you think you will need for the job. If the quantity required is large, you may opt to mix it in more than one batch. However, those decisions should be made up front rather than after the fact.
Decide what type of mortar to use. Mortar consists of cement, lime, sand and water; however, the mixture of those ingredients can alter slightly depending upon how the mortar will be used (above or below the wall line). If you are uncertain of the type of mortar to use for the job you are doing, check with experts in the field before proceeding further.
Identify where to purchase the type and amount of pre-packaged mortar needed to complete the project. Check to make certain that it has the strength needed for the project. If you plan to mix the mortar in yourself, purchase the concrete and sand separately, but make sure that you purchase the amounts needed in order to mix the formula that will work for the job. In most instances, a reasonable formula is three parts of sand to every one part of masonry cement.
Make sure that you have the materials, tools and equipment necessary to mix the mortar. Refer to the instructions on the package to identify any specific needs. These are likely to include a wheelbarrow or mortar box, mixing stick, mason’s hoe and hand trowel as well as access to water nearby.
Mix mortar in reasonable quantities. It can be easily mixed within in 5 gallon capacities, which will fit well within a standard sized wheelbarrow.
Make sure that each batch of mortar is mixed in the same way. Failure to do so could result in the construction problems.
Measure out the dry ingredients for the amount of mortar to be mixed. You can mix everything in a single container or mix it in multiple containers depending upon the amount involved. If mixing multiple containers, handle each one separately, mixing them one at a time.
Mix the sand and cement together first. Blend them together well before adding in the water.
Add any necessary tint or dye to the dry ingredients before water is added. Use the formula recommended on the tint or dye chosen in order to achieve the desired look or color.
Add in the water in quart amounts, constantly checking the workability of the mortar as you do so. There is no definitive perfect mortar mixture. Much of it depends upon the moisture content of the sand being used. The best way to determine if the mixture is correct is to check to see how it is bonding. Good mortar adheres well to the blocks and binds without easy slippage. Mortar that is too wet, however, will cause continual slippage. Mortar that is too dry, doesn’t bond well. Good mortar is about the consistency of soft mud.
Test the mortar to make certain it will hold as desired. Bond two or three of the blocks that will be used together to see how the mortar sets up. If the mortar works as planned, then proceed with the project. If, on the other hand, it does not, adjust the mortar formula by adding more dry or wet ingredients until the right mixture is obtained.
Proceed with the project, stopping to mix more mortar as needed.
Always follow the instructions provided on the products chosen. Mix thoroughly at every step.
Use safety goggles while mixing. Use rubber gloves when mixing in tints or dyes.