Surface Preparation
- The area to be repaired should be cut to provide a minimum of 1/2″ depth. Do not install repairs that have a feathered edge
- Wash the prepared surface with clean water and a bristle brush to remove dirt and dust from the pores of the masonry
- Flood the substrate with water to achieve Surface Saturated Dry (SSD) conditions. The substrate must be saturated with enough water so that it is no longer absorbent but it should be dry on the surface.
- Any water remaining on the surface should be allowed to evaporate before applying the repair product.
- Clean pail
- Potable water
- Spray bottle
- Variable speed paddle mixer
- Measuring tools
- Carving tools and trowels
- Miter rod
- Clean burlap
Application & Mixing
Mix 6 parts mortar to 1 part water. Mix only enough to use within 60 minutes using a variable speed mixer with a heavy-duty ribbon paddle and mix for a minimum of 2 minutes, and no more than three. Use a timer. As you mix the material will become more plastic and spreadable.
Apply the first layer at a depth of approximately 1/8”-1/4”” by buttering it onto the substrate.
After approximately three minutes the mixture will begin to stiffen to the consistency of wet sand. Using this remaining mix trowel the repair material on. If it becomes stiff repeat the paddle mixing process, mixing a minimum of one minute and a maximum of three until you reach the desired consistency. The longer you mix it, the lighter and smoother it will become. Do not add water.
Build the repair up over the surface of the substrate by at least 1/8” of an inch, preferably ¼”.
For the best result, wait until the mortar is thumbprint hard and does not stick to the screeding tool. This curing process will vary depending on weather conditions, so it will be important to monitor. Once the mortar has achieved the proper set screed using a meter rod to achieve a flat surface, or carve away excess mortar until the desired profile is reached. To achieve a rougher texture, wait longer before finishing.
Curing
Curing mortar should be protected with damp burlap to ensure a slow cure and to prevent flash curing. Periodically mist repairs using clean water for at least a 72-hour period. Protect from wind, hot sun, and excessive heat and cold. Optimal temperatures for application are 40-85 degrees F
Need Assistance?
Contact us at 773-598-4300 for more information and assistance.
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