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THE 4 REASONS YOUR HARDWOOD FLOORING FAILED

CONTENTS1 Introduction

2 What Causes Moisture Problems in Wood Flooring?

• Water on or Under the Floor• Humidity• Improper or No Acclimation• Improper Design or Installation

3 Signs Your Hardwood Has Moisture Problems

• Cupping• Crowning• Cracks and Separation• Buckling

6 How to Prevent Moisture Damage from Happening to Your Floor

• Acclimate Flooring• Measure the planks with a moisture meter before

installation• Use a vapor retarder to prevent moisture intrusion• Use the recommended fasteners or float system• Check the moisture condition of subfloors

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INTRODUCTIONInstalling hardwood flooring is hard. And the last thing you should worry about after you install a beautiful floor is callbacks.

Excess moisture is the biggest hid-den problem in wood flooring. It’s a gut-wrenching feeling for businesses or homeowners to find signs of moisture issues in their hardwood flooring. For contractors, getting the call that the floor failed can ruin any good day.

By knowing what issues to look for and how to prevent them, you can save your hard work and keep your customers happy.

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WHAT CAUSES MOISTURE PROBLEMS IN WOOD FLOORING?

WATER ON OR UNDER THE FLOOR

Water left on the flooring can seep into the wood causing it to swell. Spills or leaks can be common, but cleaning up the water quickly and thoroughly will save the wood. A bigger issue is when flooding occurs.

For wood that is left in flooded conditions, the repair process is lengthy.

Water coming from under the floor is likely groundwater that is not being stopped by a va-por retarder.

HUMIDITY

If the wood began with a lower amount of mois-ture and then is introduced to a high humidity environment, that moisture will be absorbed causing the wood to expand. The opposite is true that if wood with a higher moisture con-tent is introduced to a lower humidity area, the wood will shrink.

IMPROPER OR NO ACCLIMATION

Acclimating the wood is a must. Before the flooring is installed in a space, the wood needs to stabilize in an environment similar to its des-tination. Acclimating the wood prevents future expansion or contraction after installation—so long as the conditions remain constant.

IMPROPER DESIGN OR INSTALLATION

Sometimes wood planks are installed with fasteners (as opposed to a floating floor) incor-rectly, and this can restrict the natural move-ment of the wood during seasonal changes. This restriction keeps the wood from naturally expanding in humid months and contracting in arid months, which causes stress in the wood.

Lack of a vapor retarder or loss of the vapor retarder’s integrity also will contribute to mois-ture issues.

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SIGNS YOUR HARDWOOD HAS MOISTURE PROBLEMSMoisture in wood is natural. It becomes a problem, however, where there is too much or too little moisture. Here are 4 visible signs of water damage.

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CUPPING

If your wood planks have higher edges than centers, that’s a symptom of cupping. When the wood expands, there’s not enough room to expand across the entire floor, so the edges are forced together and protrude from the surface. Or, moisture is coming from below the wood causing the bottom portion of the boards to expand.

CROWNING

When wood planks have higher centers than edges—opposite from cupping—that’s called crowning. This can happen as a result of imbal-anced moisture or from a mistake in repairing cupping. If the floor was sanded prematurely, or before the moisture content stabilized, the previous cupped edges that were flattened can overcompensate and become crowned. Also, an increase in the humidity in the room can cause the wood to expand on the top surface causing cupping.

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CRACKS AND SEPARATION

Seasonal changes throughout the year affect the moisture content (MC) in wood flooring. In homes that are heated during the winter, planks shrink. Shrinking causes the appearance of sep-aration between planks to look even greater. However, this appearance oftentimes resolves itself with a change in the seasons.

Monitoring the MC in the room and making necessary adjustments can help minimize the appearance of cracks and separation.

BUCKLING

Buckling is an extreme form of moisture dam-age. This happens when wood separates from the subfloor and creates a small-scale hill or speed bump.

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HOW TO PREVENT MOISTURE DAMAGE FROM HAPPENING TO YOUR FLOOR

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ACCLIMATE FLOORING

When flooring arrives, first let it stabilize in an area with conditions similar to the end desti-nation. Some installers choose simply to wait a fixed amount of time, but the best practice is also to measure the moisture condition of the wood flooring to be sure it is where it needs to be.

To do so, you’ll need to determine what the Equilibrium Moisture Content (EMC) is for the environment in which you’re installing. Then, measure the MC in the flooring with Wagner’s pinless moisture meters, the Orion series. If you’re within 1-2 percent moisture content of the EMC reading, you should be ready to go (though you’ll always want to follow the floor-ing manufacturer’s guidelines). Bonus tip: The Wagner Orion 950 moisture meter will calcu-late the EMC for you right on the moisture me-ter using its built-in RH and temperature sensor.

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MEASURE THE PLANKS WITH A MOISTURE METER BEFORE INSTALLATION

Even after wood is acclimated, continue to monitor the planks with the Orion meters. Should the MC change before installation, take precautionary measures.

USE THE RECOMMENDED FASTENERS OR FLOAT SYSTEM

When installing the wood planks, use the cor-rect amount and specific type of fasteners. Not enough fasteners or ones that are too small will allow too much movement in the flooring. However, too many fasteners that are too large could crack the planks.

USE A VAPOR RETARDER TO PREVENT MOISTURE INTRUSION

All subfloors should have a vapor retarder un-derneath. If the subfloor is concrete, the retard-er prevents groundwater from seeping into the wood. For a wood subfloor, a vapor retarder is also necessary.

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CHECK THE MOISTURE CONDITION OF SUBFLOORS

Contractors should know the moisture condi-tion of the wood planks as well as the subfloor. For concrete subfloors, the Rapid RH concrete moisture test gets fast and accurate readings of the overall moisture condition in the slab. Exterior and plumbing walls should also be monitored.

If the subfloor is wood, the Orion pinless mois-ture meter series can get accurate readings without damaging the wood.

For most regions, if the subfloor has an MC of 12% or less, it is ready. However, if the readings are higher, address the issue and fix it before proceeding with the installation.

Enjoy peace of mind on your next job by using state-of-the-art moisture measurement tools by Wagner Meters. Be sure to check out both the Rapid RH L6 system for concrete subfloors and the Orion pinless meters for wood. For more information, call worldwide toll-free at 844-755-3365, or visit us

online at www.wagnermeters.com.