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  • Overview
  • Specs
  • Coverage Rate
  • Application

Product Description

CMW 8000 Lithium Moisture Vapor Barrier & Densifier

CMW 8000 Moisture Vapor Barrier is a clear, colorless spray applied penetrating lithium Potassium silicate blended system designed to stop concrete floor coatings and floor coverings from de-bonding due to hydrostatic vapor pressure coming up through a below grade concrete slab, on-grade slab and elevated deck slabs. This system stops hydrostatic pressure, capillary action and moisture migration by creating a negative and positive side moisture barrier.

The CMW 8000 is used prior to application of a floor coating or floor covering where excess moisture coming up through the concrete is a potential problem. The CMW 8000 may be painted, epoxied or stained over, and will accept concrete topping or mastics for floor tile etc.  The CMW 8000 is also used in joint repairs prior to application of the 3246 Expansion Joint,  our two Control Joint Fillers 3003 and 3004 to keep moisture from the joint repair.

CMW 8000 is a lithium potassium silicate blended sealer that with its small molecular structure, penetrates deep into the concrete slab. A reaction occurs between the lime and excess Portland cement, which is always present, and forms Calcium Silicate Hydrate (CSH). This process will encapsulate the moisture to create a permanent break in the capillaries of the concrete, stopping the passage of liquids and vapors through the concrete.

As a densifier, the CMW 8000 adds 20% – 40% increase in density to the concrete while increasing the strength of the cured concrete. CMW 8000 will purge alkalai salts and contaminents to the surface over a several day period and help eliminate existing effllorescnce problems from reocurring. It can also be combined with a water repellent treatment for superior protection.

CMW 8000 comes in both a Ready-to-Use and Concentrate version. The ready-to-use formula needs no mixing and can be used straight out of the container. The CMW 8000 concentrate version comes in a 5 gallon pail which makes 20 gallons & 55 gallon drum which makes 220 gallons of ready-to-use product (3:1 mix ratio – mix 3 gallons water with each 1 gallon concentrate).

For projects requiring a maximum level of moisture control or need to meet meet ASTM F3010 specifications for vapor permeance, consider using the CMW 8000 as the base level of protection followed up with a single coat application of the E1409CL Moisture Vapor Barrier Epoxy Primer or the MV2112 Moisture Vapor Barrier Epoxy Primer

The CMW 8000 adds additional protection to the E1409CL and MV2112, both of which meet the ASTM F3010 specification and can hold up 20 psi vapor pressure but in areas with significant moisture issues the CMW 8000 can help lower the potential risk of problems.  The E1409CL and MV2112 would then be topcoated with your polymeric coating or resiliant flooring system.

For crack and hole repairs in wet conditions consider our wet condition and underwater Mend-Con  RTU Epoxy Repair product.

Where is CMW 8000 used?

  • Concrete Driveways
  • Concrete warehouse, factory, retail floors
  • Basement and garage floors
  • Retaining walls & concrete tanks pre-treatment
  • Used prior to application of floor coating, covering, tile or primer
  • Efflorescence problem areas
  • Prior to application of Polyurea coating systems
  • “Out-Gassing” reduction
  • Below grade concrete – positive & negative side

Why CMW 8000 Moisture Vapor Barrier?

  • Blocks moisture vapor and hydrostatic pressure reducer
  • Used in joints to stop vapor/water pressure damage to joint materials
  • Permanent – becomes part of the concrete
  • Stops minute fracture weeping of moisture (may require several coats)
  • In areas of high humidity and salt air – reduces corrosive activity to rebar within concrete
  • Stops effloresence – purges salts and residual acidic materials out
  • Insure longer lasting floor coatings in areas of vapor pressure
  • Apply to new or old concrete
  • Improves concrete strength and chemical resistance
  • Reduce and eliminate hairline & curing cracking in new concrete
  • Assists in uniform curing on new concrete via chemical reaction
  • Acts as adhesion promoter for surface applied coatings
  • Does not change surface appearance
  • Helps concrete stains retain color longer
  • Non-toxic, non-flammable, no voc and no odor
  • Why Lithium Silicate vs Potassium or Sodium Silicates by


Color Clear, No change in appearance or surface texture
Sheen/Gloss Level None
Re-Coat When Damp 30-45 Minutes
#Coats Recommended # coats depends on porosity
Back in-service time 1-2 hours walk or drive on
Application method Low pressure hand pump or airless sprayer
Low Application Temperature 35F|1.7C Surface & Air
 Base  Water
VOC Content 0  g/L
Use on Material Concrete
Coverage Rate Square Feet/Gallon
New Fresh Concrete 325 – 400
Rough Slab Finished Surface, Cured Concrete 50 – 150
Steel Trowel Smooth Finish, High Density 150 – 250
Coverage is dependent on the profile of the surface and porosity of the substrate


New concrete should be water- blasted to clean and open the surface prior to the CMW application. Older Concrete: Remove any curing agent, form release materials, oils, wax, moisture or any material that may effect bonding. Open the concrete surface via water blasting or surface grinding. 3000 psi pressure from a water blaster @ 4-5 gallons per minute is good for dirty or stained concrete. Use a good concrete cleaner and remove all residual cleaner or soap from the surface using the above pressure.

Large Slabs & Working Surfaces:

Perform a Moisture Vapor Test using American Moisture test kit. Register results with owner or provide test result information as needed. Use ASTM F1869 Measuring Moisture Vapor Emission. Seal/repair all bug-holes, cracks and spalls, see ASTC data sheets on 830, 4034, 3004 and 830.

Application range; 40°F to 125°F. Make the application of the product as soon as the preparation cleaning is complete. The concrete surface may be slightly damp for the CMW application.

Mix the product well before applying it. For new concrete apply CMW immediately following the finishing operation or as soon as the surface may be walked on. Areas that absorb more sealer faster will need additional product applied to that area. Applications of additional coats should be applied approximately 30 minutes apart depending on drying. Multiple coats of CMW 8000 should be applied wet on wet. DO NOT allow the surface of the first coat to dry completely or additional coats may not be easily absorbed.

Each application is applied to produce a wet sheen in appearance on the concrete surface. Avoid ponding of the product and broom or squeegee excess product to areas that are absorbing more product and need additional product applied. Should ponding be allowed to remain until dry, a white scale may form and remain in areas where ponding occurred. This scale is difficult to remove.

After the last coat of the CMW is applied, spray the treated surface using clean water in two coats about 30 to 40 minutes apart. The application of clean water carries uncured product into the concrete where the product will react and remain. There is very little calcium hydroxide in the upper surface of the concrete finish and using the water is important to drive the product into the sub-surface where it will react and continue to infiltrate the concrete structure. The use of the clean water also cleans the surface and provides a good surface for the application of coatings or Water Repellants.

Allow cure time of 1 – 7 days for the product to cure before adding a surface coating. Cure time is dependent on the temperature, humidity and density of the concrete. The surface of the rinsed concrete will easily accept surface coatings as the CMW is a sub-surface treatment to block the movement of water and moisture vapor. Back-in-service time is when the surface of the concrete is dry – this is for access but not coatings per the above suggestion for cure time

Use clean water to rinse tools and sprayer unit. Avoid allowing the product to contact glazed tile, aluminum and glass

Concrete Blocks

Apply evenly using an airless spray unit. Apply additional coats as needed. On concrete block the product should be absorbed evenly, avoid excessive amounts of product and apply a second coat about 30 minutes from the first depending on the speed of drying. DO NOT allow the surface of the first coat to dry completely or additional coats may not be easily absorbed. Follow the instructions below for finishing the surface with a light wash.

High Vapor Pressure: Use approximately 4 to 5 successive coats, call ASTC for assistance. Do not allow the treated areas to dry before additional coats are applied. Moisture Vapor Barrier

Apply a primer over the CMW treated surface only when the treated concrete is fully dry. Best @ 72 hours, good @ 48 hours and minimum dry time 24 hours, dry times are dependent on temperature and relative humidity of the application environment.

Always MIX the product before using. Do not dilute or reduce/alter the product in any way. Store on wood pallets at room temperature and protect from freezing. Do not allow contact with glass, aluminum, ceramic tile, glazed tile or wood.


NOTICE TO BUYER: DISCLAIMER OF WARRANTIES AND LIMITATIONS ON OUR LIABILITY We warrant that our products are manufactured to strict quality assurance specifications and that the information supplied by us is accurate to the best of our knowledge. Such information supplied about our products is not a representation or a warranty. It is supplied on the condition that you shall make your own tests to determine the suitability of our product for your particular purpose. Any use or application other than recommended herein is the sole responsibility of the user. Listed physical properties are typical and should not be construed as specifications. NO WARRANTY IS MADE, EXPRESSED OR IMPLIED, REGARDING SUCH OTHER INFORMATION, THE DATA ON WHICH IT IS BASED, OR THE RESULTS YOU WILL OBTAIN FROM ITS USE. N0 WARRANTY IS MADE, EXPRESSED OR IMPLIED, THAT OUR PRODUCT SHALL BE MERCHANTABLE OR THAT OUR PRODUCT SHALL BE FIT FOR ANY PARTICULAR PURPOSE. NO WARRANTY IS MADE THAT THE USE OF SUCH INFORMATION OR OUR PRODUCT WILL NOT INFRINGE UPON ANY PATENT. We shall have no liability for incidental or consequential damages, direct or indirect. Our liability is limited to the net selling price of our product or the replacement of our product, at our option. Acceptance of delivery of our product means that you have accepted the terms of this warranty whether or not purchase orders or other documents state terms that vary from this warranty. No representative is authorized to make any representation or warranty or assume any other liability on our behalf with any sale of our products. Our products contain chemicals that may CAUSE SERIOUS PHYSICAL INJURY. BEFORE USING, READ THE MATERIAL SAFETY DATA SHEET AND FOLLOW ALL PRECAUTIONS TO PREVENT BODILY HARM.