Problem: Cupping or washboard appearance. Edges are higher than the center.
a) Moisture imbalance through the thickness is the ONLY cause. The material was manufactured flat when installed. Jobsite or occupant provided moisture (i.e. leaking fridge water line).
b) airborne (relative humidity) in excess of recommended minimums for an extended period of time (not very common in Calgary).
Find water leak and repair. Allow floor to dry out and resand or change water damaged boards if in a prefinished product (often prefinished flooring will sit flat after being allowed to dry out). Use a dehumidifier or proper ventilation for high relative humidity issues.
Problem: Cracking between the boards.
Dryness. The loss of moisture results in the most frequent reason for shrinkage of individual pieces and cracks. In other cases, when a floor has experienced water damage or high humidity over a length of time the edges of the wood can crush, and subsequent drying and shrinkage can present larger than normal cracks. Most cracks are seasonal – they show in dry months, or the cold season when heating is required, and close up during humid periods. This type of separation and closing is considered NORMAL. In solid 2 1/4” oak floors dry cracks may be the width of a dimes’ thickness (1/32”). Wider boards will have wider cracks.
Add moisture to the air space during dry periods (see your manufactures warranty for humidity ranges) or live with the cracks.