Moisture Barriers and Flooring


Cause and Effects of Water Vapor Transmission

The common patterns seen in concrete floors is excessive vapor transmission through concrete slabs. While we are not scientists or engineers, our goal in this article is to help you gain knowledge and better understanding so that you can become more pro-active with identifying potential issues with your current flooring.


Concrete floors are one of the largest assets in any commercial or industrial building. Concrete is not cheap and if you’re experiencing any type of floor issues as a result of water transmissions through the concrete slab, pouring a new concrete floor or slab may be your only option.

We’ve posted some pictures of moisture vapor transmission on our website for your reference or if you’re looking for some more in depth case studies regarding concrete moisture vapor transmission you can click here to Google it.

Common Concrete Floor Problems


  • Tiles coming loose on the floor
  • Blisters in seamless vinyl flooring
  • Deformed flooring
  • Moisture bubbles from floor blisters
  • Rupture of concrete slab surface
  • Gold/Brown spots on concrete slab surface
  • Moisture oozing through micro cracks in the concrete

What’s Happening?

Water and water vapor transmission through concrete slabs in our flooring can wreak havoc with the surfaces and structural integrity of our floors. Not to be confused with efflorescence, which is a naturally occurring phenomenon when water evaporates from a concrete surface salts are left behind as a powdery white material or wet or isolated stains in the floor due to workmanship problems in floor material.

As water evaporates and tries to escape the floor surfaces many forms of erosions and damage can be seen on our floors. Urethanes and epoxies can begin to bubble, blister, while the concrete can rupture or begin to show gold and brown spots. Excessive water and water vapor are the contributors to many of the failures found in flooring.

The coatings in your flooring may fail when not applied by professionals who are trained in the appropriate steps which include but are not limited to a surface survey, properly preparing the surface along with the use of superior moisture control flooring and industrial and commercial coatings that specialize in moisture vapor transmission.

Floor Coating Failures Caused by:

  1. Inadequate surface preparation
  2. Surface not properly cleaned
  3. Surface defects not corrected

Adhesion failures and coating separation is related to properly preparing the surface.

Correct preparation of the surface:


  1. Cleaning and roughening
  2. Repairing the defects
  3. Inspecting and testing the surface for defects

When these steps are not properly taken flooring epoxies will not properly adhere.

How to Perform a Surface Survey?

A surface survey should be performed in order for the coating to properly bond to the flooring. Testing for debris, dust, dirt, oils, grease, mortar splatter, curing agents, and other contaminants. If these contaminants exist the coating will not properly bond to the concrete.

Concrete grinders are used to prep and remove previous coatings, for example. Shot blasting is used for surface preparation of MMA, epoxy, urethane, and modified polymer floors.

Tip: A concrete moisture test should always be performed by a third party.

The High Cost of Overlooking the Issues of Water Vapor Moisture:

The failure to address issues of moisture in flooring, whether installing a new floor or repairing; because of lack of knowledge, time restraints, or cost can lead to many future problems or hazards. At the very least, your flooring will bubble or blister leaving an unappealing appearance. At the worst ruptures of deformed flooring can cause slips and falls or worse injuries. Industries can suffer productivity decreases or revenue losses due to clean up and damage repair.

The importance of the correct design and placement of the concrete and the best and proper installation of coating can mean a safe beautiful floor for you to enjoy for a very long time.

Advanced Floor Coatings can help you achieve the ideal flooring for your business:

Schedule a pre-construction meeting today. We can help you install new flooring or repair many of the issues discussed.

Most of these failures described here could have been prevented if proper moisture emission tests or by concrete relative humidity testing along with bond testing before the flooring was installed. Please feel free to call our office for additional information regarding these issues or for assistance with your project.

Ask your Advanced Floor Coatings Specialist if Resilient and Epoxy Flooring might be a solution for your moisture problem >

Floor Moisture Test Methods & Floor Moisture Problem Articles

American Society for Testing and Materials (ASTM)

Photo Credit: Metro Atl. Floors