When temperatures rise and fall, composite decking will naturally grow and shrink. Because of this, you should never put the ends of the boards close together. How much, then, can a composite deck get smaller? How warm the air is when the unit is put in will determine the answer.
When you build an outdoor deck, you should think about how the materials will change over time. But you might be curious about whether composite decking expands or contracts. Why do things work like this? What does it matter that you know this?
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What do materials that make up a deck do when they grow and shrink?
When you build a deck, you should think about how the boards will move as the weather changes. Most of these things happen to decks made of wood. There are other kinds of surfaces that also expand and contract. So, when putting them in place, it’s important to give them room to grow.
One of the main reasons for this is that it is humid. When wood boards are in places with a lot of humidity, they soak up water. This makes the wood grow bigger. It also happens when the deck boards get wet from rain or snow. On the other hand, boards shrink when there isn’t enough water in the wood. Because of this, decking materials are more likely to shrink in dry climates.
But here’s the question: do composites, also called wood-plastic composites, which are partly made of wood, grow and shrink?
Do composite deck boards get bigger or smaller?
When it gets hot or cold, most composite decking doesn’t change much in size across the width of the board. On the other hand, the composite decking board grows and shrinks along its length. Good composite decking shouldn’t shrink much if it’s made right. When the temperature goes up and down, composite deck boards naturally grow and shrink. Because of this, you should never put the ends of the boards close together. Then, put a fastener in the middle of each board length to keep it from moving when the temperature goes up and down.
When it gets hot or cold, composite decking tends to expand and contract along the length of the boards. When the pieces are spaced out just right, they can move without buckling.
How much does composite decking shrink and how much does it expand? People know that composite decking doesn’t grow or shrink across its width, but along its length. Or maybe just a bit across the width. Carpenters who have worked with wood before know that this is the opposite of what wood does. About 2% of wood grows along its length, but between 6-8% can grow across its width.
There are many good reasons to think about how the composite boards will expand and contract. Some of the reasons are that it’s easy to put together, safe, and the decks are far apart.
It makes it easier to put together
When the pieces are the right size, they are easy to work with. But as the temperature goes up, composite decking boards get bigger and more flexible. Because of this change, it might be harder to cut and put things together. Because the boards are getting smaller, you might not be able to stand them up.
For places where the temperature changes a lot. We suggest that when you put down your deck boards, you use surface fasteners. First, check that the deck boards are where they should be. Then, put a fastener in the middle of each board length to keep it from moving when the temperature goes up and down.
How does this help to know? The best time to put in composites is early in the morning. It’s best to stop for the day and try again the next day if it’s too hot.
Reasons why it is safe
Another reason to worry about how the outdoor boards shrink and grow is safety, especially when using nails and screws. As the boards get smaller and bigger, the nails and screws might move back up. This could hurt the deck and be dangerous at the same time.
What good will it do to know this? If you choose composite, you might want to use decking boards with grooves. You don’t have to drill or nail into the surface of these boards. Instead, the boards are held in place with clips and fasteners. If you’re still using boards without grooves, make sure the nails and screws are still in place to avoid accidents.
How to Put Deck Boards Together
Most likely, the most important thing you should know about contraction and expansion is how to space your deck boards. “Deck board spacing” refers to the space between the boards.
Since the materials that make up composite decking can expand and contract, putting them too close together can make the boards rub against each other. On the other hand, if you put them too far apart, when the boards expand, they can leave big gaps. What do you do then?
Usually, you should leave 5 to 8 mm between each board. You should also consider where you are. If you live in a hot place, the boards may shrink faster. In this case, you want to close up the space a bit. If you live in a place that is always wet and humid, on the other hand, you might want to leave more space between your decking boards.