All winter long you have been dreaming of your new deck. Now with summer BBQs fast approaching it is time to make that dream a reality. You have your plans, stainless steel screws, extra batteries for the impact driver, and a big stack of Ipe. Ready to build a deck? Ready, set, WAIT! Have you given your lumber a chance to acclimate? Don’t rush in only to have your beautiful deck, buckle and crack several months later when the summer heat and winter cold have had their way with it.
Here are some things to consider before you start cutting and drilling that Ipe, or any tropical decking:
When the tree is felled in the jungle the moisture content of the wood is 50% and higher depending on the season and the species. Once the wood has been sawn into boards it is air dried to somewhere near 20%. It is then milled into an S4S, E4E (surfaced on 4 sides, eased on 4 edges) product and shipped overseas to Europe or the US. The decking goes through some massive changes in shape and moisture content even before it is stuck in a steel container and baked on the deck of a ship for a month or so during transit.
Whether your local lumber yards imports the decking directly or not, the boards then will go through a series of climate shifts sitting in a storage shed. It may change hands a few times from importer to retailer adding further environmental changes.
Finally you buy your lumber and it is shipped or you pick it up. You will have very little idea how that decking was stored, how long it has dried, how long it has even been in the same zip code. Depending on when the lumber was sawn and how far along the decking season may be, you could be using decking that was a tree 6 months ago, or several years ago.
This is a fact of life when dealing with decking. As an exterior, air dried product this is really the only way it can be done. Your best bet is to take matters into your own hands when you buy the decking and give it time to adjust from the world tour it has just completed. Accept that it will need some time before you try to screw it down into a fixed position. The more the decking can come into an equilibrium the better off you will be in the long run.
So plan ahead on your deck project. When you receive your lumber stack it in a cool, dry place and let it sit ideally for a week, but at least for a few days. Most decking lumber is pretty long so sticking it in a garage is probably out of the question. Cover it with a tarp and “sticker” the lumber so that air can flow in and around the boards. This will speed up that acclimatization and allow you to get to work that much faster. You have invested far too much in Ipe or Cumaru to rush the job and have problems come up later with wood movement.
yes you need to acclimatize the wood prior to installing but whatever happened in its process does not really matter if you buy Kiln Dried wood (artificially dried wood). This wood is very stable and unlikely to do its own workout
Marco, for an exterior installation like a deck, using kiln dried wood can get you in trouble fast. With the wood down around the 6-8% moisture level (at least in North America) it will soak up a lot of moisture fast and expand quite a bit. We never sell kiln dried material for a deck for this exact reason. The only time we sell kiln dried material in the traditional decking species is if it is specifically for interior use applications. Just because the wood is kiln dried does not mean that it won’t soak up moisture. Kiln dried wood will move just like air dried material.
dear Shannan,
interesting reply, you know it better then we do (we are exporter, you are an installer), but when there is a client for example in France (in the North it is humid) while in the south it is dry and they almost always prefer to buy Kiln dried because they say, “then we can sell both north and south”. So, I don’t know, but this is my experience. Then, when the wood is klin dried, I understand it is able to suck up moisture, but ipe being a hardwood specie, the cells are so dense that sucking up the moisture is very very difficult and this is why I believe KD is always better no matter what surrounding climate. PS; I am talking about ipe not pine or something.
We may be on the same page Marco since kiln drying standards are different for Europe and North America. Our air dried material is usually around 18% whereas your kiln dried standard is in the 12-15% range. North American kiln dry is 6-8% so there is a wider gap between kiln and air dried on this side of the Atlantic. Let’s be real though, kiln or air dried they can both be use just as long as you give the wood some time to acclimate to local conditions before starting to fasten to anything.
My ipe has been acclimatizing for about 3 weeks now and I have to leave for a month and my deck project will have to wait till then. My wife is worried about theft so asked if we can put it in the house. We’ll raise the a/c up to 83 while we are gone to save on electric bill and so the humidity will be between 50 and 60 percent. Will acclimatize again when I get back. I can also lock up in a large shed which is insulated. Is either option acceptable?
Thanks
I had no idea that acclimating wood was so important when building with it. I have been wanting to build a deck soon so I’m glad I learned about this sooner rather than later. It’s good to know that must lumber yards will do this for you so you don’t have to worry about letting it acclimate before working. Thanks for sharing!