The House Frame

Did you Know?

When your home is constructed, the lumber contains up to 19 percent moisture.

During the first cold-weather season, your home will experience natural drying and a certain amount of shrinkage will occur. Wood expands and shrinks when the humidity changes. Minor shrinkage is normal for all wood construction and does not affect the structural integrity of your home. In many cases the gaps or openings caused by shrinkage can be attributed to temperature extremes on either sides of your homeʼs walls (i.e., interior and exterior walls). These gaps and cracks become less noticeable when more temperate weather returns.

You may notice the affects of humidity changes and shrinkage throughout your home with the appearance of:

  • Thin cracks in exposed wood structural supports (i.e., joints and beams);
  • Small gaps between countertops, cabinets, vanities and the wall;
  • Minor joint openings in door and window trim, baseboards, walls, etc.;
  • Slight separation between fireplace mantels and the walls or joints;
  • Small gaps between individual pieces of wood flooring;
  • Openings between wood flooring and wall baseboards, door jams and trim;
  • Squeaks in the underlay of your flooring and stair treads;
  • Small gaps between stairs and stair mouldings and the wall;
  • Gaps between ceiling and walls in homes that have trusses instead of attic rafters and joists.

For more information on the moisture characteristics of wood, visit the Natural Research Council of Canadaʼs website at