17th May 2022 My timber moulding has bowed, what should I do? Timber is a natural product that expands and contracts with seasonal changes and is affected by the moisture content of the air. It is important to remember that small seasonal changes in timber are considered normal and gaps that open up during dry periods are not considered defects. You can learn more about this in our product information guide. When receiving a delivery, it is recommended to allow the timber to acclimate to the room’s internal climate prior to installation.