Residential concrete moisture issues with residential flooring products in the past were difficult to deal with and very few options to work with and extensive subfloor prep. With new technology, today’s products require little subfloor prep and have a quick turnaround time.
With hardwood flooring, the options for moisture remediation have expanded greatly from Epoxy Sealers to the “All In One” Adhesives, with some adhesives now not even requiring moisture testing such as DriTac “The Golden Bullet” and Bostik’s GreenForce and Ultra-Set Single Step2. One note on these two adhesives is that the DriTac “The Golden Bullet” requires the concrete to be scoured with #3-1/2 open coat sandpaper to remove dirt or any surface contamination such as paint, grease, oil, sealers, waxes and curing compounds where the Bostik’s GreenForce and Ultra-Set Single Step2 requires the concrete must have a concrete surface profile (CSP) of 1-3 similar to a broom finish. That is a huge difference in subfloor prep. I have seen very few concrete slabs used for flooring with a broom finish. To achieve a broom finish, this will require additional prep such as shot blasting.
Where moisture issues became difficult to deal with was with residential LVT, LVP, and Sheet Floor- ing. Epoxy Sealers used with hardwood moisture issues do not work because the conventional vinyl adhesives do not adhere to these coatings. Today, we have 3 products that can be used residentially for LVT, LVP and Sheet Flooring with minimal prep.
DriTac ECO DriSeal – DriTac Eco-DriSeal is a “green”, single-component, latex based product that reduces moisture vapor transmission from concrete substrates and protects the floor covering installed.
Concrete Moisture Control:
- 1-Coat = 8-lbs per the ASTM F1869 Calcium Chloride Test Method and 80% RH per the ASTM 2170 Relative Humidity Test.
- 2-Coats = 12-lbs per the ASTM F1869 Calcium Chloride Test Method and 85% RH per the ASTM 2170 Relative Humidity Test.
This 2-In-1 product also serves to encapsulate and isolate old adhesive residue. Eco-DriSeal is an extremely easy-to-use, roller applied product that offers easy clean up. It can be used over porous concrete to help reduce penetration of the adhesive and dusting of the concrete, which results in increased spread rates and stronger bond with floor covering adhesives. Eco-DriSeal is compatible with all DriTac water-based adhesives. Eco-DriSeal can be applied over carpet adhesive residue and asphalt cutback adhesive residue as long as the adhesive ridges and raised residue have been completely removed from the subfloor with only minor stains remaining. All soft, loose and raised residue must be removed before encapsulation begins. All adhesive residue must be hard, firm and well bonded. When installing resilient flooring and carpet tiles with non-porous backings, the adhesives must be allowed to dry to the touch.
Apply using a 1/4” or 3/8” roller. Apply Eco-DriSeal in a smooth, even coat. Avoid leaving puddles. Roll Eco-DriSeal in a north-south, then east-west direction, to ensure proper coverage. Do not pour directly on the concrete. Use a roller or paint tray. Allow 3 hours dry time prior to applying second coat of Eco-DriSeal or flooring. If a second coat is desired, apply in same direction as first coat and allow sealer to dry for 24 hours prior to installation of flooring. Adhesives and patching compounds may require extended drying times when applied over Eco-DriSeal.
Note: Always install Eco-DriSeal first, and then apply patching compounds over top as directed. Drying times will vary based on porosity of the substrate and jobsite conditions. Adhesives and patching compounds will typically require extended drying times when applied over Eco-DriSeal.
Mapei Planiprep ET – Planiprep ET epoxy concrete subfloor treatment is an ultra low-viscosity, two- component, penetrating 100%-epoxy treatment designed to prepare concrete slabs for subsequent flooring installation that have been treated using Planiprep SA concrete scouring agent. Planiprep ET penetrates deeply into the prepared concrete surface, strengthening it and creating a suitable surface for direct application of all MAPEI adhesives that are approved for use on nonporous substrates. Planiprep ET must be used in a system with Planiprep SA. This product system pro- vides subfloor moisture emission control up to 12-lbs. Calcium Chloride and 92% Relative Humidity without the need for shot blasting of the concrete surface. All Mapei adhesives that are suitable over non-porous substrates may be direct bonded to a properly installed coating of Planiprep ET.
TEC The LiquiDam – Formulated to be applied to damp or new concrete, as little as 48 hours old with a moisture vapor emission rate (MVER) less than or equal to 25 lbs. per 1000 ft2 per 24 hours or a maximum relative humidity of 100%. It is designed to reduce the MVER to less than 3 lbs. per 1000 ft2 per 24 hours. One-step, single coat application that can be used with new concrete as little as 48 hours old. Install floor covering after as few as 4 hours. In existing renovation work, the concrete must be free of and surface coatings or contaminations such as *old adhesive residue.
Apply TEC The LiquiDam which cures in 4-5 hours
Apply the TEC Multipurpose Primer and let dry
Then, skim coat with TEC PerfectFinish Skim Coat
*TEC WoodStrongTM Premium Urethane Wood Flooring Adhesive, TEC Releasable Pressure Sensitive Adhesive or TEC Clear Thin Spread Adhesive may be applied directly to The LiquiDAM Moisture Vapor Barrier if concrete surface is sufficiently smooth and level.
Please note when using any of these products and removing old adhesive residue *Some previously manufactured asphaltic “cutback” adhesives contained asbestos. For removal instructions, refer to the Resilient Floor Covering Institute’s publication Recommended Work Practices for Removal of Resilient Floor Coverings.
The million dollar question then becomes, how do I know if I have a concrete moisture problem? With every concrete subfloor you should be testing for moisture and documenting your results. In my travels, many dealers will use the Tramex Moisture Encounter to check all their concrete subfloors. If the reading exceeds 4, they do one of the two the recommended moisture tests for resilient flooring, the CalciumChlorideortheRHProbeTesttoseeexactlyhowmuchmoistureisintheconcrete. https:// www.tramexmeters.com/store/moisture-meters-flooring/Tramex-Concrete-Encounter-CME4-Moisture-meter-for-concrete