Concrete Slab Testing & Inspection

C.L.I. Group, LLC can perform the required testing before your finished flooring is installed to assure that the application will not pose problems later. We will also perform inspections of failed flooring systems to determine causes and make repair recommendations.

Having the required testing performed by a qualified third-party consultant prior to flooring installation is the best way to avoid costly flooring failures. The manner and standards of the testing should be clearly spelled out in the specifications for the project. The acceptable moisture levels should also be clearly stated, as should the consequence of test results indicating excessive moisture.

Why Flooring Fails

There are many reasons for floor failures in both new and existing buildings. There are also many floor failures which could have been prevented with a proper evaluation by a third party consultant during construction. In many cases it may be long after construction is completed and the building is handed over to the owner before flooring failures become apparent.

Moisture and alkalinity are the two most frequent causes of flooring failures. This may be due to construction schedules, a lack of testing, poor workmanship, etc. It is important that the architect specify, very clearly that all concrete which is going to receive finish flooring be properly tested (by a third-party consultant) before installation. It is much more cost effective to perform the testing in advance as opposed to skipping it and having problems later which will require mitigation, testing and possible replacement of a damaged flooring system. Many do not understand that there is a difference between moisture resistant and alkalinity. A floor adhesive may perform well under moisture condition but fail due to high alkalinity.  Therefore moisture levels may be low and the floor fails due to a high pH level. Both moisture content and pH should be tested prior to installation.

Moisture Redistribution

C.L.I. Group, LLC believes that in order to build a complete picture of moisture levels in slabs, more than one type of testing must be performed on that slab. While most construction specifications and manufacturer literature calls for performing slab testing using ASTM-1869-04 (Calcium Chloride). We believe that the calcium chloride test may need to be supplemented with additional information gained using In-situ probes at a depth of 40% of slab thickness. Concrete slabs dry from the top down and therefore may contain high levels of moisture below, while the surface meets the 3lb. requirement of most manufacturers. The moisture that lies beneath the surface redistributes toward the top of the slab after the floor covering is added. This accounts many times for higher moisture readings at the surface of a slab after damage has occurred.

Concrete Slab Inspections

This test requires the use of a gram-weight scale with a gradation of 1/10th (0.1) gram. The calcium chloride container is weighed before and after exposure to the concrete slab. It is highly recommended that the test be weighed prior to, and directly after exposure on the same scale. This is a very sensitive and highly accurate test when conducted properly. Differences between two scales and extended time between weighing can offset the test result.

C.L.I. Group uses a calibrated, electronic gram scale for performing on-site measurement using the same scale both before and after placement to assure accuracy.

pH (alkalinity) Considerations

Fresh concrete contains alkaline components which result in high pH, which is bad for the concrete and equally as fad for finished floor. These alkaline components typically leach out of the concrete during the curing stage. However, if the slab has not been allowed to properly cure, these alkaline components can wreak havoc of your slab and finished flooring. While many flooring adhesives are immune to moisture and perform well, this is typically not the case with high alkalinity. Most adhesives will fail when exposed to excessive alkalinity. This is a major reason why proper curing of the slab before floor installation is so important. Your consultant should also be testing the pH levels of the concrete when performing moisture testing. 

In-Situ Probes

C.L.I. Group uses a Protimeter MMS for perform the In-situ testing on concrete. Our system can measure the Equilibrium Relative Humidity (ERH) in solid floors, walls and many other materials using embeddable humidity sleeves. It measures both the relative humidity (RH) and ambient temperature of an environment, along with calculating the dewpoint temperature which is also critical to understand in the placement of finish flooring materials.

ASTM F2170-02 requires the ambient conditions above the slab should be at service temperature and humidity for at least 48 hours before testing is carried out. It is also required that the instrumentation should be within 5^o F of the building service temperature to ensure fast and reliable readings.

ASTM F-2170-02 requires (3) sleeves to test for the first 1000 ft² and at least 1 sleeve test for every additional 1000 ft2.

Additional Testing Methodologies

C.L.I. Group also utilizes many datalogging pieces of equipment in evaluating buildings. The Protimeter Humilog is used to measure and log parameters such as temperature, relative humidity, surface temperature, moisture levels and dew-points. This allows to monitor conditions over time.  This is an excellent piece of equipment for monitoring condensation conditions, remedial drying procedures or construction activities such as the application of finished flooring.

Many problems in construction today can be traced back to the moisture levels of materials during construction, construction schedules which do not allow for proper drying of materials, poor moisture management during and after construction and poor selection of materials.

The process of monitoring the above described parameters is just one more area where C.L.I. Group, LLC follows the "total building commissioning" concepts which are a common theme throughout this web site.

It is during our testing & commissioning that our field technicians measure, map and document the performance of critical and integrated building components. Our philosophy encompasses the building as a whole philosophy. All of the major integral components of any building must operate as a whole with all other systems and components. When any of these major systems fail or is changed, it can affect the operation and performance of the other integral systems and cause premature system degradation as well as other problems.

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