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Moisture Reduction Strategy



Moisture reduction strategy
As outlined by the
National Wood Flooring Association (NWFA)

  1. I. PURPOSE
    1. 1.1. The purpose of this procedure is to advise customers and/or installers on how to improve high moisture conditions. Uncorrected elevated site moisture often result in performance issues with flooring such as cupping, crowning, tenting, finish peeling, delamination, etc.
  2. II. SCOPE
    1. 2.1. This procedure should be followed prior to installation. It may also be implemented post-installation if moisture issues develop.
  3. III. PROCEDURE
    1. 3.1. If you have a crawl space, it is imperative to have 6 to 8 mil black plastic on the ground. It must be overlapped 6" at the seams and extend approximately 6" up the walls. Weigh the plastic down with a heavy object such as rocks or bricks.
    2. 3.2. Ensure that the yard is graded so it allows water to flow away from the home foundation. Gutters enhance floor performance as well and must remain clog free. 
    3. 3.3. The effects of the treatment below may take one week to one month to improve high moisture conditions. It is imperative that this is corrected prior to installing flooring. If your flooring is already installed, follow this procedure. Often, moisture-related issues with the floor will self correct.
    4. 3.4. Turn the A/C fan to "on" position and maintain @ 72-73 degrees.
    5. 3.5. Use 2 Commercial Size dehumidifiers:
      1. 3.5.1. Place one in your crawl space or basement. Make sure the tube is routed away from the home, down a hill, or in a drain to ensure that the moisture does not reenter the structure.
      2. 3.5.2. Place one on the main floor. Make sure it is emptied frequently, or routed to a drain.
    6. 3.6. Contact your local rental business or another water damage restoration company to rent an air movement fan. Many will bring the fan to you and set it up. This should be used in the main area of the home, as it blows the air across the floor. "Seal the envelope" by closing windows and doors and closing vents in the crawl space. This will ensure that the HVAC and humidifiers are operating at maximum efficiency.
    7. 3.7 Purchase temperature / humidity controlled fan and set it so that it will turn on when the relative humidity reaches about 45%. Place it in your crawl space or basement. Continuing to run a dehumidifier (for the long term) in humid climates or a humidifier in dry climates will enhance the floor's performance.
    8. 3.8 Monitor the following conditions until the desired target is achieved.
      1. 3.8.1 Relative Humidity (RH) in the crawl space - max. of 45 - 50%
      2. 3.8.2 Relative Humidity (RH) in the room(s) where the flooring will be / is installed - max. of 45 - 50%.
      3. 3.8.3 Moisture of the flooring - domestic 6 - 9%; exotic 6 - 11%.
      4. 3.8.4 Moisture of the sub floor:
      5. 3.8.4.1 2 " wide - within 4% of the flooring.
      6. 3.8.4.2 Greater than 2 " wide - within 2% of the flooring.
      7. 3.8.5 Moisture of the floor joist in a crawl space should be a maximum of 14%.
    9. 3.9 Require your installer to record this information for your records. Allow installation only when these guidelines are met.
  4. IV.QUALITY RECORDS
    1. 4.1. Documented moisture and relative humidity readings from item 3.7 above.
  5. V. DEFINITIONS
    1. 5.1. N/A
  6. VI.REFERENCE DOCUMENTS
    1. 6.1. Technical Publication No. A100 (National Hardwood Flooring Association (NWFA)), "Water and Wood"
    2. 6.2. Supplied by Dan Blake, All Flooring Inspection Co.

Technical & Installation Support 02/2016