As a wood floor naturally expands and contracts with changing humidity and temperature levels, you may hear small cracking or squeaking noises. In the winter your wood floor will tend to Contract and it will Expand in the summer. This is why you will notice more small gaps in your flooring in the winter months. To lesson the chance of noises and gaps always try to keep your relative humidity around 35-55% (for most wood floors). Please check with your manufacturer for your specific product humidity requirements. Maintaining a constant temperature and humidity all year long will lessen the expanding and contracting. This may mean that you have to run the AC or Heat a little longer than you'd like or even invest in a whole house humidifier / dehumidifier. Follow the link below to see what Lowe's has in stock near you.