Florida Hardware Fall Market, August 11-12, 2018; Orlando, Fla.

Water is an inherent part of the hydration process of physical. Nonetheless, assuasive backlog wet to get out the slab after it's poured is crucial to a successful flooring installation.

Once the slab is poured, the excess moisture must exit the slab in order to strengthen the physical bond. The slab must also dry to a specified level of moisture before flooring materials can be installed on meridian of it. Moisture-related damage to the flooring materials is possible.

iii Common Floor Materials Run The Risk of Moisture-related Problems:

1. Adhesives
   Moisture-related adhesive failures are a problematic reality in the flooring business. Contempo trends towards restricting volatile organic compounds (VOCs) in floor adhesives take increased the number of moisture-sensitive adhesives used. If the adhesive used to install the flooring does not have the right moisture tolerance for the concrete subfloor, the entire installation can be at risk.
2. Floating Floors
   Floating flooring systems are attractive because they don't need to be attached directly to the subfloor. Instead, the flooring pieces "lock" together to become a cohesive unit that'south non every bit vulnerable to seasonal shifts, dimensional challenges, or other moisture-related issues. In fact, floating floors are often recommended on projects where moisture risks are high with standard attached floor systems. For floating floors, manufacturers often recommend installing a moisture barrier between the subfloor and the floating floor to forbid moisture intrusion. The difficulty, of course, is that if the moisture bulwark is compromised in any way, moisture from the slab beneath can all the same damage the floor or end.
3. Grout or Cementitious Bonds
   Excess moisture issues in a grouted tile or mosaic flooring often appear as efflorescence, a whitish residue on the surface of the grout. It's the outcome of h2o-soluble minerals getting transported to the surface of the grout with the wet every bit information technology evaporates abroad. Since minerals don't evaporate, they're left behind on the floor surface as a visible residue. The more porous the concrete or grout, the more likely efflorescence will appear. In the majority of cases, these minerals are actually role of the concrete slab mixture. Although they can maybe be in the basis beneath the slab, and seep into the physical if no moisture bulwark was installed. If the slab was not dried to the required specs before the tile was installed, the natural moisture migration of the drying concrete will impact the grout. Remediation steps will be necessary to correct the problem. In farthermost cases, excess moisture can lead to flaking or chipping of the grout which results in a complete grout or thin-set failure.

Are you seeing a theme nonetheless? The existent risk to a successful flooring lies with the moisture that tin can accumulate inside the layer between the concrete slab and the flooring itself.

summary
Adhesives, floating floors, and grout or cementitious bonds are iii common flooring materials that can run the adventure of causing moisture-related problems. Wet control is oftentimes one of the most crucial, nonetheless most overlooked, elements of whatsoever floor's success over time. Responsible wet control (having accurate moisture measurements) starts with the physical slab.

Make sure to use the most accurate concrete rh test from Wagner Meters.

Shop Rapid RH L6

Click to scout and larn more well-nigh moisture issues between flooring and slab.

Wet in a Concrete Subfloor

For moisture to accumulate betwixt the concrete slab and the flooring, it needs to notice its mode to that middle layer. In this section, we breakdown the primary ways water tin go into your physical, which causes a buildup of excess moisture, and listing effective methods to forbid moisture problems from occurring.

Sources of Moisture in Concrete

The primary source of moisture in a concrete slab is the proportion of h2o mixed with the cement. No water source has a greater impact on the time it volition take concrete to dry.

Yet yous have other water sources to worry near. A variety of potential external water sources at a worksite can bear upon slab drying and curing.

• Rain, snow, and sprinkler systems are culprits on a piece of work site open to the elements. These water sources increase in danger if the grade of the grounds around the slab slope towards it. Non only is the physical absorbing the water from above, but information technology's also taking on the runoff from the areas around it.
• The concrete slab can too blot the groundwater below and around it. Thus, the amount of natural groundwater has a huge impact on concrete moisture weather condition.
• Unnatural water sources tin can as well leak water. Whatsoever poor plumbing installation at the worksite creates a loftier take chances of excess moisture. Quondam plumbing that's degraded and has leaks presents the same take a chance.
• Ambient atmospheric condition tin besides increment the physical slab's water content. Condensation develops on a slab that has a lower temperature and moisture level than the air's dew bespeak. The dew point is the temperature at which the air can agree no more moisture. You know, when dew (or condensation) starts to class. The slab volition absorb some of the condensation.

  The slab will besides absorb moisture from its surroundings when its relative humidity (RH) is beneath the air's RH. Moisture wants to level out. If the air holds more than wet than the slab, equally evidenced by its RH, that wet volition move to the physical.

summary
Rain, snowfall, groundwater, leaks, increasing h2o content, and sprinkler systems are all potential sources of free water. That is, water the concrete doesn't demand to cure. Any moisture the slab doesn't need is moisture that can undermine your flooring installation.

What Are Causes of Excess Moisture in a Concrete Slab

Inadequate drainage around the slab exacerbates the run a risk of any source of wet. In fact, the existing water source itself may not exist the problem. A footling rainfall or a fleck of groundwater can drain away with well-designed drainage. Even minimal sources of water can pool on the concrete without adequate water lines and drains.

Excessive water can too intrude in a structure due to poor subfloor protection. Groundwater will move into the concrete if no vapor retarder sits between the basis and the subfloor.

The more than likely crusade for poor subfloor protection is using the wrong vapor retarder. Certain ASTM standards let a vapor retarder to have a perm rating of 0.iii perms, which could permit upward to "approximately 18 gallons of water per week in a 50,000 square foot surface area." A vapor retarder with too low a perm rating won't practise the job information technology needs to practise.

In other cases, the vapor retarder may have been sitting on the footing. It's helpful to accept a separation barrier between the ground and vapor retarder. Contractors should install the vapor retarder over granular fill to create extra separation from the groundwater.

A torn vapor retarder is another potential hazard to subfloor protection. Torn vapor retarders can occur in a reckless worksite. Hurried construction schedules create all sorts of moisture (among other) threats.

Fast-paced project plans often hateful that physical slabs don't become the time they need to dry. For example, slabs may become ability troweled to speed upward preparations for flooring. The pinch caused by the troweling closes off the evaporation outlets in the slab. The event is that over troweling will extend the drying time.

If the schedule doesn't permit for that time, so adhesives or surface membranes get installed on concrete with too much moisture. A moisture-related flooring failure is practically guaranteed under such circumstances.

Complimentary Download – 7 Things You May Not Know about Concrete Slabs

How to Avoid Backlog Wet

The best of intentions to avert excess moisture doesn't affair if you lot don't have accurate concrete moisture testing. There are two main means to suffer inaccurate moisture testing. The first is to cull the wrong concrete wet test. But the in situ RH test measures wet below the slab's surface. Any test measuring simply surface moisture is necessarily providing inaccurate results.

The other fashion to become inaccurate wet test results is to perform the in situ RH examination wrong. If y'all don't place plenty sensors throughout the floor, y'all won't get an accurate moving picture of the space.

ASTM F2170 requires three sensors for the first 1000 foursquare feet and another sensor for each additional 1000 square anxiety. Other testing mistakes include non inserting the sensor to the proper depth.

Serious errors can fifty-fifty occur from simply miswriting readings on your chart. The Rapid RH® L6 sensors contain integrated data storage that automates results reporting. When the coming together takes place to make up one's mind when to install floor, no 1 has to rely on paper notes.

Make sure to use the most accurate concrete rh test from Wagner Meters.

Shop Rapid RH L6

How to Prevent Moisture Problems on Physical Floor

Wet is an inevitable office of concrete construction. Moisture-related problems are not.

• Keep a low water to cement ratio. The more h2o in the mix, the greater the chance the slab won't get all the time it needs to dry. Try to avert adding water to concrete that's already mixed. That h2o is a new variable that makes managing timelines and moisture bug difficult.
• Have all necessary deportment if pouring concrete below grade or at a wet building site. Whether that means installing more draining lines, using pumps to dewater the site, or any other method – do it. Brand sure that your water displacement methods aren't generating run-off in the wrong directions.
• The layers in a higher place and beneath the concrete slab to forbid water seepage into the slab. Start with a vapor retarder with a perm rating that reflects the needs of the space. Install it over a layer of fill. Inspect it earlier pouring the concrete and fix whatsoever tears it may have. If necessary, use a proper underlayment betwixt the concrete slab and the floor. This is especially true when using wood flooring. Installing a plywood underlayment can add extra protection, merely must besides be tested to ensure information technology'due south not bringing in new wet.
• Give the concrete slab the time it needs to dry and cure. Review the projection program and schedule. Is plenty time gear up aside for concrete floors to dry? No reason to start out behind the eight ball. Exert as much control every bit possible over the ambient conditions to accelerate the timeline. Protect the space from outside elements. If the flavour isn't platonic, can you take steps to reduce swings in air temperature? Will a dehumidifier help the air absorb more moisture from the concrete? Use fans to increase airflow, which speeds up drying time.

All these methods point towards a single goal: non installing whatsoever flooring too soon. Preparatory materials similar adhesives or plywood will seal up the concrete. Sealed concrete will stop releasing moisture. At that point, the slab has the moisture information technology will hold for the long term. If in that location's backlog moisture trapped in the concrete, information technology will somewhen reveal itself in ugly and perhaps dangerous ways.

summary
Low water to cement ratio, using pumps to dewater, not using a vapor retarder, and not allowing concrete to adequately dry and cure are all means to prevent wet problems on concrete floors.

How to Tell If There Is Excessive Wet in My Flooring

A floor may already be showing some external signs of containing backlog wet. A flooring with a white or greyish powdery stain (as well chosen "efflorescence") likely has excess moisture. Due to moisture moving upward through the slab and then evaporating from the surface. The whitish stain is the salt left behind by evaporating water. Or yous may come across that the flooring installed over the concrete slab is blistering or peeling away. If a forest flooring has been installed on top of the slab, the wood may be bang-up or warping. These types of flooring failures occur due to excess moisture trapped between the flooring and the concrete.

No one wants to wait until the ugly signs of excessive wet make themselves visible. You desire to know if your flooring is holding also much moisture well before that.

The calcium chloride test is an older method for measuring the moisture level of physical floor. Information technology's too called the moisture vapor emission charge per unit (MVER) test. Information technology'south standardized every bit the ASTM F1869 (Standard Test Method for Measuring Moisture Vapor Emission Rate of Concrete Subfloor Using Anhydrous Calcium Chloride).

The MVER test uses the weight differential over a 72-60 minutes catamenia of calcium chloride salt placed on the slab'south surface. The calcium chloride, sitting under a sealed dish, absorbs the wet evaporating from the slab. You calculate the rate of evaporation based on the weight differential.

Unfortunately, ambient conditions often corrupt MVER exam results. F1869 doesn't even let its utilize on lightweight concrete. Of greater concern is what the MVER test measures. It measures wet only at the surface of the physical slab. It's not testing the wet condition that matters over the long haul. You need to know the moisture condition within the concrete.

Only the in situ RH tests for wet beneath the slab's surface. Sensors inserted into the slab mensurate the RH within the concrete.

And these aren't random depths. ASTM F2170 (Standard Examination Method for Determining Relative Humidity in Physical Floor Slabs Using in situ Probes) specifies the depth based on whether the concrete is poured on form and whether vapor retarders are used.

Rigorous scientific testing conducted at universities and laboratories has determined and validated the proper depths. At the proper depth, the RH sensor accurately reflects what the moisture condition of the slab will exist in one case the flooring is installed.

The Rapid RH L6 returns the scientifically reliable readings you need to consummate a successful flooring project. Readings that the MVER test can't provide. Even better, the RH test can be completed in 24 hours. That's one-third the waiting time required to conduct an MVER test.

summary
Excess moisture is caused by a number of means a few existence: the hardwood floor is cupping or cracking, yous run across efflorescence or a white residue on the concrete floor, or the floor over the concrete is blistering or peeling away.

Wet Management Requires Accurate Wet Readings

Accurate physical moisture measurement is simply achieved with RH testing. Unlike surface-based tests like calcium chloride tests, RH testing determines the accurate wet condition within the slab past placing probes at a strategic and proven depth. Wet oftentimes rises through a slab from the bottom to the top in the drying process. Merely testing performed at the correct depth can let you determine if the final wet condition of the slab volition be uniform with the flooring and the products used to install it.

Wagner Meters has been assisting floor professionals for over fifty years. During these decades, nosotros take designed some of the most accurate, innovative, and easiest RH testing sensors on the market today. The Rapid RH L6 is the newest iteration, taking reward of 21st-century applied science to simplify reporting.

All our Rapid RH sensors and test kits are based on decades of scientific research and technological advances to help each builder and flooring specialist accurately determine the right concrete RH level for a project's chosen flooring materials. Our innovative Total Reader® and manufactory-calibrated Smart Sensor blueprint delivers quick, reliable results. The Rapid RH line of products is affordable and conforms to ASTM F2170 requirements for easy recording and reporting.

Nosotros too understand that sometimes a building project schedule ways making alternate choices in adhesives or even flooring products. The Rapid RH sensors aid you brand informed decisions in real-time. Along with authentic, actionable testing, nosotros've too compiled a one-stop listing of manufacturers that provide an RH tolerance specification for their flooring products at www.rhspec.com.

The truest way to protect a floor system is to ensure that all components are safe from excess moisture intrusion from any source. The Rapid RH family unit helps yous forbid your concrete slab from being the source of a wet-related floor adhesive or grout failure. Don't let moisture bug come betwixt you and a successful flooring installation.

Are you looking for a concrete figurer to estimate how many cubic anxiety and cubic yards of concrete you will demand to fill your space? Try out our concrete calculator.

Jason has 20+ years' feel in sales and sales management in a spectrum of industries and has successfully launched a variety of products to the market, including the original Rapid RH® concrete moisture tests. He currently works with Wagner Meters as our Rapid RH® product sales manager.

Concluding updated on January 26th, 2022

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