Thread: Minor Soil Movement

Client called saying she had cracks in between her hardwood floors. Client explains the cracks appear in winter with low humidity and disappear in summer with high humidity. Flooring contractor claims it is a foundation issue.

So I checked the crawlspace to find some minor soil movement. Particularly around the piers.

The cracks were 1.5 inches wide and 12 inches deep! The cracks were up to 5 feet long and were over an area approximately 12-15 feet square. Guess where the 1/8 inch cracks in the hardwoods were? Also notice the lack of vapor retarder.

Similar Threads:

• "Shrink-swell soil" article. Did inspector miss this?
• Asbestos found in Bozeman homes, soil - KPAX-TV
• Fungal growth in/on soil in sub-area
• White stuff on soil
• Fungal growth in/on soil in sub-area

Originally Posted by Bruce Ramsey

Client called saying she had cracks in between her hardwood floors. Client explains the cracks appear in winter with low humidity and disappear in summer with high humidity.

This is normal movement for floors and is to be expected.

From woodfloorsonline.com:

Cracks and separations between boards
Nearly every floor endures some separation between boards. In winter, when homes are heated and the air is dry, wood flooring gives up some of its moisture and therefore shrinks. When that happens, thin cracks appear between. This is normal, and homeowners should be forewarned of this. It is acceptable, and customers should not be calling the installers at the first sign of cracks. Once the indoor heat goes off in the spring, and the indoor environment regains moisture, most of these cracks will close up.
Cracks in winter--in the drier months--may easily develop to the thickness of a dime (1/32 inch) for solid 2 1/4-inch wide strip oak floors. Floors with light stained woods and naturally light woods like maple tend to show cracks more than darker, wood-tone finished floors. The cure for cracks? Homeowners should add moisture to the air during dry periods. It's their choice-live with the cracks and wait until spring, or else add humidity by opening the dishwasher after a rinse cycle, switching off the bathroom fan or hanging laundry to dry in the basement near the furnace. Better yet, install a humidifier in the furnace, or an exterior air vent for the furnace burner.

What surprises me is that the flooring contractor said it was a foundation issue.

If the footings were below the back fill material (the 12" deep is odd) it is most likely not an issue if there were no other signs of movement in the house, doors not closing, drywall cracks, etc...

Originally Posted by chris mcintyre

This is normal movement for floors and is to be expected.

What surprises me is that the flooring contractor said it was a foundation issue.

If the footings were below the back fill material (the 12" deep is odd) it is most likely not an issue if there were no other signs of movement in the house, doors not closing, drywall cracks, etc...

I asked leading questions to find out the cracks appeared and disappeared and told the client over the phone before accepting the job that is normal and caused by seasonal humidity. She said she still wanted to pay because the floor guy said it is not a floor issue but a foundation issue.

The soil movement had jiggled the piers and opened up a crack 1/8 inch between some of the flooring. There was some other minor cracking of interiors.

I just had never seen cracks in crawlspace floors this extreme before.