Does Wood Expand In Cold? (Here’s The Truth!)

does wood expand in cold?

When we are working with wood to make furniture, carving, and all other types of woodworking stuff, we always wonder how weather affects my wooden applications especially when it is cold.

So, let’s figure it out, “Does Wood Expand in Cold?”.

Here is what I found after years of working with wood:

No, Wood does not expand in cold. It only shrinks in cold. All the wood types on earth follow the same rule, expand when heat and shrink/collapse when cold. Wood shrinks in cold due to the moisture content difference between the atmosphere and the wood itself, not because of temperature variations.

But that’s just a quick snapshot of the question.

There is a lot more to know about how cold affects wood applications, the expansion of wood in winter, what happens to the wood when gets wet, and what are some common things that we could expect when the wood in cold.

So, in this article, we’ll dig into all of them and try to find answers with my experiences.

So, let’s keep going!

Does Wood Expand In Cold
Patio furniture in cold weather

How Does Cold Weather Affect Wood Furniture?

Cold temperatures are not bad for your furniture only if they don’t face constant temperature fluctuations from hot to really cold.

If you live in an area which doesn’t have rapid change from extreme cold to extreme hot weather conditions during the period of the year, you no need to much worry about wood furniture.

But if your wood furniture faces constant temperature fluctuations, sorry to say Cold weather conditions are particularly bad for wood furniture if you are not careful.

As with every other material wood also expand when heated and shrinks when cooled and the same theory applies to furniture made out of wood.

Constant temperature fluctuations can damage wood furniture because of expansions and contractions. After several expansions and contractions, your furniture will start warping which can cause more trouble.

My advice is never to leave wood furniture in a cold garage in storage. During the daytime, we feel that nothing bad will happen because of the sunny environment with a high-temperature level.

Once the sun goes down the temperature will rise dramatically to a freezing level, especially in winter.

Does Wood Expand In Cold
Wooden fence in winter

I have experienced that wood will start to warp day by day because of these temperature fluctuations because wood expands in the daytime and contracts when cold during the nighttime.

This can significantly reduce the lifetime of wood furniture. But well build furniture won’t get damaged easily because of the cold temperature level.

If you have no plan to keep your furniture protected over years, this is not even a problem, because it can take more than decades to cause any damage depending on the type of wood your furniture is made of.

This is the reason why some antique furniture will show cracking and warping over years of facing extreme hot and cold weather conditions after several warping and contractions with the temperature levels.

Do Wood Floors to Expand in Summer?

Yes, Like wood furniture, wood floors also expand in summer and contract in winter.

Expansion of Wood in Winter

As I mentioned earlier, the wood starts to shrink to its smallest dimension with the arrival of winter.

Expansion of wood happens under high-temperature levels during summer. Wood shows completely opposite behavior during the winter season with contractions.  

According to my personal experience, in the spring and fall, the wood and its applications will expand half of its maximum movement allowance and tend to contract the other half.

The main reason for this type of expansion and contraction of wood with hot and cold temperature levels is because of humidity.

During winter the humidity of the atmosphere (76%) is significantly higher than the humidity in summer which is 66%.

This humidity change causes wood to shrink or expand. Constant shrinking and expansion of wood with seasons cause the wood to crack.

The good news is the expansion of wood with temperature fluctuation only applies to real wood.

If you’re a person of interest using wood alternatives such as MDF, Plywood, or Chipboard you need to have zero concern about expansion or contraction during winter or summer with temperature fluctuations because they never affect this issue.

Does Wood Expand In Cold
Patio furniture in winter

How Long does it take Wood to Expand?

Wood is hygroscopic matter and it absorbs moisture under several circumstances. According to the humidity of the air, wood tends to absorb moisture and expand.

When the wood is denser it takes more time to absorb the moisture, because its stability is higher than less dense wood.

Hardwoods that are high in density will take longer for moisture to penetrate through the surface. Softwoods that are low in density absorb moisture quickly because they are having a high porous fiber structure.

When the wood less dense they absorb moisture and as a result that they expand much faster than wood with high density.

The same goes with contraction. When the level of humidity goes down, less dense wood will release moisture much faster than hardwood.

Because of this quick response to the environmental humidity with cold and hot temperature levels, softwood and furniture that are made out of softwood tend to crack easily than hardwood furniture and their durability is also particularly low.

However, there is a limit of wood expansion and a limit of moisture content that each wood can absorb. Moisture content will never increase to 50%.

My advice is you to, if you willing to keep the furniture over 50-60 years even under extreme weather conditions and temperature fluctuations, always use good quality hardwood because they have a great amount of resistance and strength.

Does Wood Expand In Cold
Door panels in winter season

Wooden doors Expand and Shrink in Winter

I get a lot of questions why are wooden doors easily closed in the summer and not in the winter or rainy season?

This can explain perfectly by using humidity as a factor. When it’s cold outside the humidity level of the atmosphere is low.

When the humidity outside is low, the moisture that is trapped inside wood doors will penetrate outside to balance the humidity between the inside and outside of the wooden door.

As a result of the penetration of moisture to the outside, the wood will start to shrink. This will happen under normal circumstances.

But there are certain conditions that we see wooden doors expand in winter.

Think if we hang our wet coat or jacket or any other wet surface near that door during winter, then moisture will start to penetrate outside from that coat or jacket because outside humidity is pretty much lower than the interior.

As a result that the moisture content of the atmosphere near the wooden door will increase, which means the humidity will increase.

Once the humidity level near the wooden door surpasses the internal humidity level, the moisture will tend to penetrate to the inside of the wooden door even under cold temperatures in the winter or rainy season.

As a result of this penetration, the wooden door will expand. This same incident can happen when the snow has set right in front of it due to the unbalance of humidity. This is how wooden doors expand even in the winter seasons.

By closely looking at the above two examples we can see that Does Wood Expand in Cold? Mostly not but could be under special circumstances. Even though its cold or hot wooden door behaves differently according to the level of humidity inside and outside.

Does Wood Expand In Cold
Wooden door in cold weather

How to Deal with Wood Expansion?

Expansion of wood in cold or hot weather conditions is a natural uncontrollable process. But there are some steps we can take to fix this problem to protect our woodwork and furniture.

  1. Sealing the wood airproof. Sealing wood can prevent expansion. use polyurethane resin, epoxy resin as the sealer and after applying several coats your wood will airtight and it won’t absorb moisture from outside which causes expansion. by following this method, you’ll be able to stop the expansion but not the movements. I highly advise you not to stop wood movements, because wood is a hygroscopic material, and it needs to balance its humidity level according to the outside environment.
  2. Constant temperature fluctuations happen during the transition period from season to season (Winter to Summer). We can disassemble our important furniture during this transition period to prevent them from cracking or warping.
  3. Don’t expose your furniture to the outside for a long period of time. You should pay special attention to the wood storage boxes in your garage because they easily in contact with the outside environment.
  4. Always use quality hardwood to make furniture that has high stability and has very good resistance to environmental changes. Well build furniture can keep even outside for a long period with zero protection.

From all the above methods, you’ll be able to stop or slow down the expansion of wood in cold and hot temperature levels.

But the most practical method that I recommend is to seal the wood airtight by applying polyurethane, epoxy resin sealer 2-3 times above the wooden surface.

By doing this you’ll be able to increase the lifetime of furniture pretty much you want.

Does Wood Expand In Cold
Window panels in winter

That’s it. Hope you learned everything you wanted to know about, Does wood expand in cold?

Let’s answer some frequently asked questions.

What Happens To Wood When It’s Cold?

Wood tends to contract when it is cold. Cold weather negatively affects the physical properties of wood. Due to the random contractions all over the wood, it will shrink and warp pretty quality.

Excessive warping causes wood to crack and split due to the dimensional movements.

You need to be careful when placing furniture outside under cold weather since the dimensional stability can loose due to the contractions of wood under extreme cold weather.

What Time Of Year Does Wood Expand?

Wood tends to expand under hot weather. During the spring and fall seasons, wood will expand half of its total movement allowance and contract the other half.

June, July, August are the months that wood tend to expand due to hot weather.

What Time Of Year Does Wood Shrink?

Wood tends to expand under cold weather. During the Winter season, wood will shrink half of its total movement allowance and contract the other half.

Does Wood Expand At Night?

Yes, wood expands slightly at night.

During the daytime the moisture inside the wood evaporates from the wood to the air since the humidity inside the wood is higher than the humidity outside.

But at night humidity in the outside air is higher than the humidity inside the wood.

Therefore, moisture ten penetrates the wood through pores at night.

When moisture enters the wood, the fiber cells will swell and expand. Because of this expansion of cells wood expands at night time.

Does Wood Expand In Monsoon?

Yes, wood expands in monsoons.

During monsoons, the atmospheric moisture level is higher than the moisture level of the wood inside.

in order to balance the humidity difference between the outside and inside of the wood, the water molecules will penetrate the wood through its pores.

When moisture enters the wood, the fiber cells will swell and expand. Because of this expansion of cells wood expands in monsoon.

Does Sealing Wood Prevent Expansion?

Yes, sealing wood prevents expansion since the sealer coat work as a barrier between the wood and outside air.

The moisture in the air blocks from penetrating wood due to the sealer. Therefore, water particles won’t enter the wood and prevent wood expansion due to sealing.

that’s why sealing is important, especially before placing the wood furniture outside.

Moisture inside the wood won’t evaporate and outside moisture won’t penetrate the wood due to the selling coat.

The sealer protects wood from water damage and rotting.

Did I cover All You Wanted to Know About Does Wood Expand in Cold?

We learned about more than the expansion of wood in cold in today’s article.

We talked deeply about Does wood expands in cold? Expansion of wood in winter, How long does it take to the expansion of wood, Expansion of wood in a cold environment with special cases, and How to stop wood expanding with real-life examples.

I have included everything I know about the expansion of wood to make this article rich.

On top of that, we even dug deep to find the perfect method to prevent the expansion which will extremely helpful for your future woodworking projects!

Wood tends to contract in cold weather. It does not expand in cold weather. During cold months, to balance the water level outside and inside of the wood, the water particles will evaporate from the wood. Due to the lack of water inside the wood, wood tends to shrink in cold weather.

Remember, always select quality food and the most suitable wood type according to the application you’re going to use that.

Warping and cracking can happen due to continuous expansion and contraction of wood and they are not repairable which means can damage your furniture forever!

Walter Parker is a woodworking enthusiast. He is passionate about woodworking projects & plays with woodworking tools having spent over 2 decades as a leader for Woodworking Planet. He wants to make people love woodworking! Read More About Him!

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