Healthier Choice CHOICE Hardwoods - Manual (Page 3)

RECOMMENDATIONS FOR EQUALIZING SOLID WOOD:
• Flooring stored upon “on-grade” concrete floors should
be elevated at least four inches to allow air circulation
under cartons.
• Flooring must acclimate for as long as necessary to
meet minimum installation requirements for moisture
content. Using the equilibrium moisture content chart
below, determine the proper moisture content for the
installation.
• Always use a moisture meter to determine where the
flooring and present job-site conditions are in relation to
the projected final equilibrium point taking into account
seasonal changes.
• Monitor the flooring and job-site conditions as they
acclimate. If the wood is neither gaining nor losing
moisture, an equilibrium condition has been reached.
NOTE: No single fixed moisture content is right for all sites as equilibrium points can vary dramatically in different environments. It is
the responsibility of the owner and installer to monitor all variables that can impact the target equilibrium point.
TESTING FOR MOISTURE CONTENT
The determination of moisture content is an essential part of quality control within the flooring installation process. Flooring installers
must know the dryness of not only the wood flooring, but its sub-floor and the concrete slab beneath it, if one exists. A moisture meter
is a critical tool to determine if floor boards are dry enough for an installation to proceed. Moisture is one of the most critical areas of
concern. Monitor the flooring and the job-site conditions throughout the preparatory period and the installation process. The sub-floor
must not exceed 12% moisture content and the difference between sub-floor and hardwood flooring cannot exceed 4% for 3-5/8”
planks and 2% for wider planks. If a sub-floor exceeds this amount, an effort should be made to locate and eliminate the source of
moisture before further installation. A moisture barrier (6 mil polyethylene film minimum) may be required in addition to the 15 lbs.
asphalt felt. Asphalt felt is not considered a moisture barrier.
SUB-FLOOR PREPARATION
The sub-floor must be structurally sound. The sub-floor must be dry and free of wax, paint, oil and debris. Replace any water-dam-
aged or delaminated sub-flooring or underlayment. Scrape smooth and sweep prior to installation. The sub-floor must be level, that is,
within 3/16” over 10’ and/or 1/8” over 6’. If the sub-floor is concrete, a minimum of 30 days drying time for a reliable moisture reading
is necessary. DO NOT use gypsum-based (white) patching compounds. Follow the manufacturer’s recommendations for applying the
leveling compound. Areas containing new leveling compound must be completely dry (meeting moisture vapor emission tolerances)
before proceeding with the installation of the wood floor. If the sub-floor is plywood or equivalent, high areas or joints must be sanded
flat. If plywood or equivalent, the sub-floor must be properly secured with nails or screws every 6 inches along joists to reduce the
possibility of squeaking after final installation. Appropriate moisture tests must be performed as outlined in the “Testing for Moisture
Content” section listed below. Minimum thickness sub-floor material recommendations are satisfactory for 16” on center joist spac-
ing. Thicker sub-floor recommendations will allow up to 19.2” joist spacing. Sub-floor panels should be spaced 1/8” apart to allow for
expansion. It is highly recommended that Choice Hardwood solid floors not be installed over existing glue-down wood floors or over
wood floors that exceed 3 1/4” face size. Cover sub-floor area with 15 lbs. asphalt felt. If installing over subfloor, use vapor retarders
such as asphalt, saturated craft paper or 15lbs. felt.
NOTE: Over a wood subfloor do not use an impermeable vapor retarder material with a perm rating of ,7 or less, such as 6 mil
polyurethane film or other polymer materials, as it may trap moisture on or in the subfloor.
Equilibrium Moisture Content Chart
C: -1 4 10 16 21 27 32 38 43 49 54
F: 30 40 50 60 70 80 90 100 110 120 130
5 1.4 1.4 1.4 1.3 1.3 1.3 1.2 1.2 1.1 1.1 1.0
10 2.6 2.6 2.6 2.5 2.5 2.4 2.3 2.3 2.2 2.1 2.0
15 3.7 3.7 3.6 3.6 3.5 3.5 3.4 3.3 3.2 3.0 2.9
20 4.6 4.6 4.6 4.6 4.5 4.4 4.3 4.2 3.0 3.9 3.7
25 5.5 5.5 5.5 5.4 5.4 5.3 5.1 5.0 4.9 4.7 4.5
30 6.3 6.3 6.3 6.2 6.2 6.1 5.9 5.8 5.6 5.4 5.2
35 7.1 7.1 7.1 7.0 6.9 6.8 6.7 6.5 6.3 6.1 5.9
40 7.9 7.9 7.9 7.8 7.7 7.6 7.4 7.2 7.0 6.8 6.6
45 8.7 8.7 8.7 8.6 8.5 8.3 8.1 7.9 7.7 7.5 7.2
50 9.5 9.5 9.5 9.4 9.2 9.1 8.9 8.7 8.4 8.2 7.9
55 10.4 10.4 10.3 10.2 10.1 9.9 9.7 9.5 9.2 8.9 8.7
60 11.3 11.3 11.2 11.1 11.0 10.8 10.5 10.3 10.0 9.7 9.4
65 12.4 12.3 12.3 12.1 12.0 11.7 11.5 11.2 11.0 10.6 10.3
70 13.5 13.5 13.4 13.3 13.1 12.9 12.6 12.3 12.0 11.7 11.3
75 14.9 14.9 14.8 14.6 14.4 14.2 13.9 13.6 13.2 12.9 12.5
80 16.5 16.5 16.4 16.2 16.0 15.7 15.4 15.1 14.7 14.4 14.0
85 18.5 18.5 18.4 18.2 17.9 17.7 17.3 17.0 16.6 16.2 15.8
90 21.0 21.0 20.9 20.7 20.5 20.2 19.8 19.5 19.1 18.6 18.2
95 24.3 24.3 24.3 24.1 23.9 23.6 23.3 22.9 22.4 22.0 21.5
98 26.9 26.9 26.9 26.8 26.6 26.3 26.0 25.6 25.2 24.7 24.2
R
elativ
e Humidity %
Ambient Air Temperature
3