One of the most iconic images of a job site is workers mixing material in a wheelbarrow. But this common task is actually a driver of unnecessary costs, time and materials.
Often, these workers are mixing aggregate into mortar, extending the mortar to achieve the proper viscosity. But ultimately, this age-old method is just that: old. There is, in fact, a better to properly use the materials.
Available to any contractor these days, mortars pre-extended with aggregate eliminate the need for a contractor to source aggregate locally and add it at the job-site when project requirements call it. Here are a few factors to consider:
Locally sourced aggregates can be mixed with undesirable fine particles or other contaminants. Certain aggregates react to alkalis found in cement mixes and will swell, deteriorating these repairs over time. This Alkali Silica Reactivity (ASR) is an important reason to choose mortar with coarse aggregate added at the factory, where quality control is a major focus. Another issue to watch out for is “pop-outs” caused by contaminants in the aggregate reacting with the mortar. This results in hunks of mortar literally popping out of the main repair, leaving an unsightly and exposed chip in the finish.
Many repair mortars require extra aggregate to accommodate placement at thicknesses beyond what the neat material can achieve. Aggregate can be obtained locally in both bag and bulk to extend the materials for these applications, but locally-sourced aggregate present can cause logistical, quality and workflow issues, such as coordinating delivery at the job-site, separate on-site storage to protect it from the elements, as well as contamination from construction debris and dust.
Balcony repairs accessed by a swing-stage where space is limited and safety is paramount, the convenience of a pre-extended mortar is unrivaled.
Water addition rate
If the aggregate is not uniformly hydrated, this will wreak havoc on the mixture. Workers trying to dial-in the water content are forced to adjust from batch to batch, wasting time and likely resulting in overwatering, which must be discarded.
If the aggregate needs to be added at the job-site at the point of mixing, how is the aggregate being portioned? Is it being accurately measured or just eyeballed via a few shovel loads? Variability with aggregate addition rate will ultimately cause water demand variability.
Imagine the fluctuation in water demand caused by the combined effects of variable aggregate wetness and poorly portioned aggregate addition. Having aggregate already added in the material eliminates this frustration — and any potential quality and finish problems — for the contractor.
Download our data sheet for MasterEmaco 1061EX rapid-setting cement-based pre-extended concrete repair mortar.
This material is not just a more convenient option. The advantages of pre-extended mortar can make a real difference in profit margins when you consider these potential benefits:
Looking for more tips on using a pre-extended mortar? Check out this short, on the job application video.
- Labor savings
- Water demand remains consistent – no tinkering to dial in water due to wet aggregate
- No measuring or weighing of coarse aggregate
- No logistical headaches sourcing and staging aggregate for the job
- Quality of coarse aggregate assured as it is added at the factory