Wood Characteristics

Moisture Effects

Affects of Moisture in Wood

  • Any solid wood product will expand over time as moisture and climate conditions change
  • Effects of moisture may include:
    1. Panel expansion
    2. Joint expansion or opening (especially on miter doors)
    3. Stile bowing
    4. Panel contraction (may result in ?white line? if finished)
    5. Stile/rail expansion

Southern or Humid Climates

  • Southern or humid climates are especially susceptible to expansion due to moisture
  • Locations include:
    1. Waterfront properties
    2. Coastal regions
    3. Gulf coast, especially Florida
  • Marine applications, such as boats and yachts, are considered high humidity regardless of any climate control systems
  • Non-air conditioned homes, regardless of location, are very susceptible to expansion due to moisture
  • Winter and vacation homes should maintain some form of climate control, even in off-season

Tips for Avoiding Moisture-Related Problems

  • Certain wood types, primarily Hard Maple, have a tendency to expand more than others. For details, see chart
  • If expansion in doors occurs prior to installation on cabinet box, air conditioning will usually return doors to normal

Potential Wood Movement Chart

This chart indicates how much a 12" wide panel can change in size depending on moisture.

Wood Type Width in inches at
5% humidity
Width in inches at
14% humidity
Wood movement in inches caused by 9% swing in moisture
Red Oak 12 12.29 0.29
Hard Maple 12 12.27 0.27
Soft Maple 12 12.27 0.27
Cherry 12 12.23 0.23
Hickory 12 12.29 0.29

In general, Merillat manufactures its products at a moisture content of 6% to 8%, depending on the season.