Addressing Concrete Moisture Issues with Pene-Krete® Products
Excessive moisture is the number one reason why coatings fail, so it’s critical for installers to understand and address it.
The reality is that all concrete has moisture exposure to some extent. Moisture also comes from many sources. It could come from the soil, a sprinkler system, a crack in a pool or broken water pipe. Concrete is literally like a giant sponge and will suck the moisture right out of the air.
Testing for moisture is always required prior to applying concrete coatings. Personally, I treat all concrete for moisture regardless of what my moisture readings are telling me. Moisture readings can vary greatly throughout the year depending on ambient temperature, humidity and air conditioning methods.
You’ll hear me say it time and time again: proper surface preparation is the most important part of any system. And by “surface preparation,” I’m not only referring to a concrete surface profile, removing existing coatings or having a porous substrate. Yes, those are all very important requirements for properly preparing the surface to be coated, but the absolute most important step is to address the moisture.
To combat moisture issues, Super-Krete® Products developed S-1300 Pene-Krete®, a penetrating densifier for use on all concrete and masonry substrates. It reacts with alkali and free lime in common cement and creates an internal crystal-like shield, increasing the strength of new and existing concrete and masonry, and reducing moisture vapor transmission.
To mitigate moisture with Pene-Krete, take the following steps. We are going to assume the concrete is already free of existing coatings or bond breakers, structurally sound and porous.
Start with S-12000 Heavy Duty Degreaser™
A commonly overlooked step in the moisture mitigation process is degreasing. I’m often asked, “If the concrete was just poured 28 days ago, why do I need to clean it?” S-12000 Heavy Duty Degreaser™ does more than just clean the concrete. It extracts deeply penetrated oils and other contaminants out of the concrete that could eventually deteriorate your bond and delaminate your coating. It is going to introduce a high alkalinity to the concrete, improving its soundness and strength. This high alkalinity is also going to promote a better reaction with the Pene-Krete as it reacts with the alkali and free lime in the concrete.
The degreasing process is simple:
- The typical application is to spray the degreaser with a hand pump sprayer at a rate of 300-square-feet per-gallon while scrubbing it into the surface with a stiff bristle broom.
- More degreaser can be applied in heavily saturated areas.
- Allow the degreaser to penetrate the concrete for about 30 minutes.
- The degreaser can be simply rinsed off with a standard water nozzle, but for best results it should be washed off with a high-pressure water blaster.
- On interior applications, the degreaser can be mopped up with clean water or lightly rinsed while controlling the water with a wet/dry shop vacuum.
Apply S-1300 Pene-Krete
Pene-Krete penetrates and reacts with the alkali and the free lime in the concrete. Upon immediate contact with the surface, Pene-Krete penetrates and forms a gel within the concrete that eventually hardens into a crystal-like shield within the capillaries of the concrete. This process densifies the concrete and drives any existing contaminants and salts to the surface. In heavily contaminated concrete, you may see a residue from the Pene-Krete purging it to the surface.
Although Pene-Krete effectively densifies the concrete, we do not promote it as a densifier. It should not be used for polishing, as it may purge contaminants to the surface in the form of efflorescence. The purpose of Pene-Krete is to significantly reduce the moisture vapor transmission (MVT), which is the passage of water through the concrete, to acceptable levels for coating. It has many additional benefits, including:
- Increases the compressive strength of the concrete up to 23%
- Increases coating life up to 300%
- Protects reinforced steel from rust
- Preserves and strengthens fire-damaged concrete
- Stops efflorescence
- Eliminates dusting and chalking
- Prevents freeze/thaw damage and thermal shock
- Resists mold and mildew
- Reduces the permeability of the concrete
- Eliminates carbonation attack
- Improves the concrete’s resistance to uric acid
- Reduces shrinking, cracking and curling on freshly poured concrete
- And more
Now let’s get started with the application process:
- Step 1: Pene-Krete can be applied on the same day as the degreasing. You do not want any standing water on the surface, but the concrete should be damp upon applying the Pene-Krete. If there are any puddles or standing water after the degreasing process, simply squeegee and/or blow the puddles off of the surface with a leaf blower. If the concrete is completely dry, lightly dampen the surface with water.
- Step 2: Pene-Krete is then spray applied at the rate of 300-square-feet per-gallon. As one person is spraying and completely saturating all areas of the concrete, another person is brooming the material into the surface. If any puddles occur during application, be sure to immediately broom the material into an unsaturated area and keep moving.
- Step 3: One hour after the application of Pene-Krete, you want to completely saturate the concrete with water. You do not need to flood the surface, just saturate it. This can be done with a hose or a hand pump sprayer. This is to be done a total of three times in one-hour intervals. The purpose of the water is to force Pene-Krete deep into the concrete. Test results have shown penetration as deep as 8.5 inches into the slab. You want to ensure full depth penetration to properly treat the concrete for moisture. The Pene-Krete application is a one-time application. It is not a film forming sealer, and it will wear with the concrete over time.
Based on the success of Pene-Krete, we have developed a few other products to tackle some other applications, depending on the work you are doing:
- S-1400 Pene-Krete Additive – Pene-Krete Additive is a highly concentrated version of Pene-Krete that is designed to be mixed with fresh concrete at the time of the pour. It can be added at the plant so that it mixes on its way to the jobsite and is ready to pour when it arrives. It can also be added at the site and mixed for five to 10 minutes at high speed prior to pouring. Only a single gallon of Pene-Krete Additive is required for a full 10 cubic yard concrete mix.
In addition to all of the benefits listed above with Pene-Krete, the Additive comes with these additional advantages:
- Allows concrete to reach its full strength before 28 days and allows you to coat concrete on the eighth day after pouring.
- Reduces the temperature of the mix, allowing you to save hot loads.
- Gives the finishers more time and workability when finishing the concrete.
- Acts as a lubricant and makes cleaning out the concrete trucks easier, as the drivers can simply rinse their mixers clean with a water hose.
- S-1500 Concrete BOOST!™ – Concrete BOOST! is a single serving solution to working with individual ready-mix concrete bags. Like Pene-Krete Additive, Concrete BOOST! is designed to be mixed with the concrete, but on a smaller scale. It’s available in 2 oz units. One 2-oz unit is mixed with a 60-90 lb bag of ready-mix concrete. No additional measuring needed in the field. Easy peasy.