Often asked: Does Wood Shrink Or Expand In Winter?

Expansion of Wood in Winter Expansion of wood happens under high-temperature levels during summer. Wood shows completely opposite behavior during the winter season with contractions. This humidity change causes wood to shrink or expand. Constant shrinking and expansion of wood with seasons cause the wood to crack.

Does wood expand when cold?

Wood is a pretty challenging building material; it burns, it rots, its strength varies depending on which way the grain is oriented and it is sensitive to temperature and humidity. Heat will make wood expand and cold will make it shrink, potentially causing cracks or loose joints.

What happens to wood in the cold?

Wood can expand in colder temperatures and it can also contract in colder temperatures. Wood doesn´t directly contract or expand because of the surrounding temperatures but because of its internal humidity level. So, as weird as it may sound, wood can contract as well as expand in the cold.

Does timber shrink in winter?

The Secret to Successful Woodwork. Changes in temperature and relative humidity cause wood to expand or contract, explaining why wood expands in winter and contracts in summer. Most timber shrinkage or expansion occurs across the grain (ie across a plank).

Does wood shrink or expand as it dries?

In dry weather, wood shrinks as any remaining moisture in the cells walls evaporates. In a warm, humid atmosphere, the cells reabsorb moisture from the air and expand. An 8-foot-long green board may shrink up to 3/32 inch while being air or kiln dried.

Does wood warp in the cold?

The temperature itself is not an issue, as wood does not shrink or swell due to temperature changes alone. Adjusting manufacturing humidities and wood MC levels for cold wintertime weather is prudent to avoid warp, open glue joints, cracking and so on.

Which way does wood expand?

Direction Matters Wood only expands and contracts in one direction; perpendicular to the grain. Depending on the specie of wood you’re working with, it can move as much as ¼”, or even more. You don’t need to worry about expansion and contraction parallel to the grain.

How much does wood expand with temperature?

Wood at intermediate moisture levels (about 8% to 20%) will expand when first heated, and then gradually shrink to a volume smaller than the initial volume as the wood gradually loses water while in the heated condition.”

Does dry wood expand in heat?

When timber is subjected to heat, it expands. This process is known as thermal expansion and can cause warping, swelling and potentially shrinkage. Wood can perform much better under heat stress than several other materials that you might consider to be hardier.

How do you make wood expand?

How to Make Wood Expand

1. Expose the wood directly to water to force it to expand.
2. Raise the humidity of the air around the wood to increase the moisture level in the wood and cause it to expand.
3. Cool wood that has been heated by underfloor heaters or other similar heat sources to expand the wood.

Does wood expand or contract when wet?

Wet air expands wood, dry air shrinks it. Use a moisture meter to note the highest moisture content (MC) in your wet season and the lowest in your dry season.

Does wood expand lengthwise?

Wood moves as its moisture content changes. Wood doesn’t move much lengthwise, so you don’t have to worry a lot about boards getting shorter. But a board can move quite a bit across its width. A board that’s 6 inches wide during a humid summer might shrink by 1/32 of an inch in winter.

Do wooden doors expand in winter?

Removing an exterior door for repair during the winter is something nobody looks forward to. Seasonal changes in temperature and humidity cause wooden doors and window frames to expand and contract.

What time of year does wood expand?

Wood shrinks to its smallest dimension in the winter and swells to its maximum in the summer. The wood in winter projects will expand; the wood in summer projects will contract. In the spring and fall, remember that the wood will expand half your total movement allowance and contract the other half.

Does a house expand or contract in winter?

Why Wood Expands and Contracts The wood framing, doors, trim, and floors will shrink under conditions of low humidity (most often the winter) and expand under conditions of high humidity (most often the summer). Usually, these conditions will return to normal when the humidity returns to normal.

How much does wood expand with moisture?

In wood this averages about 28% but will vary by a few points depending on wood species, specific tree and even individual boards. As wood dries below this moisture content it shrinks until the moisture content reaches equilibrium with its surrounding environment. lumber is 12% to 15%.