Timber Floor Cupping

The cupping is due to some type of moisture imbalance in the wood flooring itself.

Timber floor cupping. The simplest way to think of wood floor cupping is to imagine the edges of each plank sticking up higher than the centers. The general effect is easy to demonstrate by putting a small strip of paper onto a small drop of water. It ends up looking a little like an accordion. Cupping is a common problem found in hardwood floors.

Site related causes of wood floor cupping. Boards will remain cupped. Moisture from below can. If you imagine a picture of a child drawing a boat in the water then the water will give you a good idea of what a cupped floor looks like.

Cupping means that the wood that is raised on the edges of each individual floor board. Wood is hygroscopic in nature and thereby tends to absorb moisture from its surroundings causing problems in hardwood floors. The sides of each board are higher than the middle sections. It is not hard to see the effect in wood flooring either.

This makes the wood appear to be in a u shape. As you can see moisture and wood don t go well together. See the picture at the top of this post for an example of a cupped floor. Wood is hygroscopic so it gains or loses moisture in your home seasonally.

Wet maintenance can cause cupping. The center of the board dips below the edges. Water vapor emissions from concrete. This imbalance could either be moisture from the concrete environmental conditions in the space being to dry and drying out the top of the wood and or a wood floor that wasn t properly acclimated to the environment prior to installation.

The paper will curl up away from the water. As the name implies the surfaces of boards that suffer from cuppinghave a concave shape. There are a number of potential causes of site related wood floor cupping. Any wood floor can suffer from cupping.

Cupping occurs in solid wood flooring as a result of an elevated mc in the bottom of the flooring compared with the mc of the face. Wet crawlspaces and basements will cup a floor as moisture moves upward. How our 950 moisture meter works is it has a hygrometer built in to read temp humidity and calculates your the emc equilibrium moisture content of what your wood floor should be. When the moisture increases the wood swells and then when it decreases the wood shrinks.

Cupping can also occur in rooms with dry humidity. Increase the relative humidity in the room with cupped floors to 20 percent to prevent cupping from the air being too dry. Wood cupping develops a set in boards ultimately boards that have cupped due to these moisture differences develop a set and remain cupped even when the boards have dried. Cupping dry or wet wood floors can be caused by humidity lack of humidity temp water.

You can observe this dramatically in an interior wood floor that has been flooded then dried. Cupping in solid wood floors.