Floor Moisture

Ever find yourself out on the shop floor wondering where that puddle came from?
Does your slab sweat?
Have you been cited for failure to maintain a safe and slip free atmosphere?
Ever notice mold and/or mildew forming beneath your carpet or tile…or actually growing directly out of your concrete slab?
Having a problem getting your flooring to stay in place?
Was your slab poured prior to 1983?
 WPplasticsheet

If you answered YES to any of the above questions, you probably have a moisture problem.The flooring industry has multiple methods for testing the moisture content in your slab. Any reading over a 3.0 means that you have some form of moisture working its way from the ground up through your slab. A moisture reading between 3.1-6.0 are relatively common and can be easily handled with proper treatment. A reading of 6.1-12.0 requires a more aggressive approach and readings over 12.0 are considered extreme. Left untreated, floor moisture can cause multiple problems including floor covering failure, mold, mildew, efflorescence, structural wood rot, water damage to furnishings and a host of other issues that can be a financial drain.

A few probable causes for slab moisture are: The presence of a high water table, broken water pipes within the slab, deteriorated underlayment, environmental air pressure, humidity, rain and more. In the below picture you will see an extreme case of vapor transmission and the efflorescence it causes. It is more common here in Texas that will will find efflorescence in smaller quantities under rugs, wood flooring, or in storage areas where plastic bins have been stored over a section of the floor for a period of time.

001 floor moisture

For most cases in the Gulf Coast region of Texas this is often a combination of factors and most often identified in homes and businesses that were built on a slab on grade foundation from 1960-1983. The reason for this is that during that time a tar paper or sometimes even a plastic underlayment was used to block water from under the slab but as time has revealed this was not a long lasting solution and this underlayment has since deteriorated and left the slab vulnerable to capillary action, vapor transmission and other hazards of water transmission.

The common misconception is that concrete is a solid surface, however, concrete is very porous and filled with little microscopic tunnels similar to a sponge. When the air above the slab is very hot and dry water or water vapor will naturally transmit to the surface, equally, when the air above the slab is humid and wet, this same vapor may push down into the surface. This is why pet owners often experience the scent of pet urine long after its first appearance.

Have no fear, there are options for remediation of floor moisture. If you suspect a problem, start with a moisture test to determine your best course of action. At Slip Free Systems we always try to determine if there is a moisture problem prior to your installation but we encourage you to share any suspicions or point out evidence of floor moisture that you are aware of as concrete floors are tricky in that they sometimes show signs of vapor transmission during a wet season and sometimes not during a dry spell.