How To Mix and Install Self-Leveling Concrete

Recommended Tools:
1. Mixing Drum – should be large enough to accommodate 2 or more bags of material and water.
2. Spreader (Application tool used to gauge thickness of material to be placed)
3. Steel Smoothing tool
4. ½” heavy duty drill (650rpm min)
Surface Preparation:
1. Make sure concrete substrate is clean and all grease, oil, asphalt, sealing and curing and latex compounds have been removed. Any possible contaminant should be disposed of, removed or cleaned. Depending on the condition of the concrete mechanical cleaning may be necessary to expose sound, clean concrete.
2. Self-Leveling concrete requires a primer to be applied prior to application. This is to ensure a good flow and well-finished surface. Apply the primer with a clean soft-bristle push broom. Use of a paint-roller is discouraged as the broom application allows the primer to get into the pores of the existing surface. All areas should be primed and excess puddles should be brushed off.
3. The primer should be allowed to dry to a tacky, thin film. No less than an hour and no more than a day’s drying time will be sufficient.
Mixing:
1. Measure out the manufacturers recommended water dosage and pour into mixing barrel. Hold back one part (approximately 10%) of the water during initial mixing to minimize powder lumping. Most products mix better with a minimum of 2 bags of product at once unless you will not need that much material.
2. Add dry powdered material into the barrel. If you are mixing using a hand drill it should be turning as you add the concrete.\
3. Mix thoroughly with drill for approximately 30 seconds and add remaining water until desired consistency is reached. Continue mixing for another 1 and a half to 2 minutes to obtain a lump-free mix (this is especially important with self leveling concrete mixes as they are applied very thinly and even small lumps in the mix can mess up the finish as well as other undesirable effects. NOTE: Yellowish foam while mixing or settling of the sand during placing indicates over-watering!
Application:
1. Pour the leveling concrete mix on the slab and spread the material with the spreader. Adjusting the spreader to allow ¼ “ of material to be placed on the substrate is recommended. To obtain the best flow install material at a minimum of 1/8 “ over the highest point in the floor. This method will typically result in an average thickness of ¼ “ over the entire floor. Typical product flow times average 10 minutes at 70 degrees. Once the initial pour has been established, product can be feather edged.
2. Immediately after placement, smooth the material with your steel smoother. This will break surface tension on the concrete and allow the material to better flow into marks left by the spreader and applicator spikes. It will also leave a finer finish and minimize pinholes.
3. Take precautions to avoid blowing air on freshly placed concrete to prevent plastic shrinkage cracking and other undesirable effects.
4. Typical self-leveling concrete products are ready for light traffic in 4-5 hours at 70 degrees though this depends on humidity and substrate temperature.
5. As always, follow proper curing guidelines to get the most out of your project!

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