Expansion and contraction of wood is perfectly normal during changes in the weather. Wood is a natural material that seeks to be in balance with its surroundings. Hardwoods destined for use in home furnishings are carefully kiln-dried for that purpose, and they will take on or give off moisture with extreme changes in relative humidity. When the air is exceptionally warm and humid, solid hardwoods will absorb moisture and expand. Likewise, with much cooler, drier air, the wood will give off moisture and contract. This is completely natural, and craftsman design fine solid hardwood products to accommodate these changes.