Why Wait?

carpetWe often times get questions from our clients about timing of the installation of floor coverings over a new concrete slab. Their question is Why Wait? As you know, concrete is manufactured by mixing cement, aggregate, and water in appropriate amounts in order to create a precise consistency. As the water evaporates out of this mix the concrete hardens or cures to the desired strength. The goal is to get the excess moisture to evaporate from the slab into the air, so that the curing process can be complete. This is a process that can take days, or even weeks. So the answer to the question Why wait? It is all about the moisture…

  • Trapped moisture will cause floor coverings to fail. The speed of the evaporation will be determined by the temperature and humidity of the surrounding air. It will also be affected by the size of the pores in the concrete. As long as the vapor pressure in the slab is greater than that in the air, water will continue to evaporate from it. If excess moisture is present in a concrete slab and an impermeable floor covering is installed, such as carpet or vinyl tile, the moisture will become trapped under that covering. Over time, hydrostatic pressure will force that moisture upwards causing damage to your floors.
  • Trapped moisture will cause adhesives to fail. Moisture-related adhesive failures have always been a problematic reality in the flooring business. In addition, with recent trends towards restricting volatile organic compounds (VOCs) in flooring adhesives, there has also been an increase in the number of moisture-sensitive adhesives in use. If the adhesive being used to install the flooring does not have the correct moisture tolerance for the concrete subfloor, the entire installation can be at risk.

Understanding that there is a wait time for when flooring adhesives should be applied can be crucial to the time line of a project. PDMi can help you through the process of identifying that wait time on your next building project. Give us a call, we’d love to help…

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