What Causes Interior Paneling to Warp?

Paneling is any wood or composite material used as a liner on a surface. Cheap panels are made of inexpensive plastic and paper composites, whereas more expensive versions are made of wood and veneers. Several homes have wood and vinyl paneling installed as decorative elements. Warping is considered any change to the geometric structure of a panel. Several factors cause panels to warp.

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Wood paneling is the most common type of decorative home accent.

Humidity

Wood grows and shrinks with hot and cold. The material attempts to obtain a balance of moisture within the wood and moisture surrounding the wood. High humidity raises the water level in the wood, forcing the structure to expand. A drop in the humidity causes the wood to contract. Repeated exposure to high and low humidity will eventually lead the wood to warp. Radiant heat within a home causes a heightened level of humidity. Coastal regions naturally have a heavy fluctuation of moisture throughout the year. Protecting from humidity requires proper sealing of the material prior to installation. Sealants provide a barrier to wetness, allowing the wood to maintain a more stable level of internal moisture.

Thickness and Density

The thickness of material adds to the warping. A denser wood is more prone to warp. Plywood panels warp for similar reasons. A sheet of plywood has a core surrounded by the wood fibers, which provides the stability for the sheet. A thicker core is less prone to warp, but the warping still occurs due to moisture exposure. The denser woods will flex more, and the thinner cores on plywood are less structural stable. Purchasing lightweight solid wood panels or plywood sheets advertising core thickness between 50 and 70 percent of the total thickness of the sheet gives you the best option to prevent warping.

Improper Construction

Paneling is put up using combinations of glue, brads and nails. The glue creates a bond with the subsurface that will hold the panel in place. The brads and nails allow the wood to maintain the position on the surface. When the materials flex, the nails and glue hold the position. Using insufficient amounts of glue, or spacing the nails or brads too far apart, leaves gaps that will cup and causes twisting of the material. A good rule is to insert nails or brads along each stud while applying glue liberally and evenly across the back of the surface.