The question of proper drying method for Ipe decking lumber is really a non-issue: kiln-dried Ipe decking is essentially the same as air-dried Ipe decking. However, environmental conditions at your job site will be important to consider, where moisture levels and movement are concerned. Hopefully we’ll be able to help you understand why.
One of the most significant environmental factors relating to your deck is the amount of direct sunlight to which your deck will be exposed. When direct sunlight hits a deck, it acts to quickly force moisture to be shed from the boards, potentially causing warping. One way to ameliorate this potential problem is to make sure the boards you install are on the drier side; in addition, you can cautiously plan for proper ventilation and appropriate gap spacing.
Now if kiln-dried and air-dried Ipe decking contain the same percentage of moisture content, you may be wondering how to ensure your decking boards meet the above-mentioned requirement of being on the dry side. There’s no short cut: you must allow for an acclimatization period in which your boards are allowed to come into an equilibrium with the immediate surroundings in which they will be installed. The boards will naturally absorb or shed moisture in order to adapt to their new environment. While they’ll continue that process as seasons and precipitation and sun exposure continues to shift, this initial acclimation is significant.
The term “air-dried decking” can sometimes come into play here: some people think that it’s better for the majority of the country, while “kiln-dried decking” is more appropriate for unshaded decks in warmer climates or those in especially dry areas of the country. But remember: they are one and the same. This misconception may be widespread and certainly makes sense, considering that most kiln-dried material is dried to a lower moisture content, but that rule of thumb is not true for kiln-dried decking lumber. In fact, because of the confusion surrounding this issue, kiln-dried Ipe decking may be referred to as air-dried Ipe decking. Sorry about that. But really, it’s all the same, anyway. Decking boards will be dried to the higher moisture content of 14-18% — whether the process is expedited via a kiln or not.
Here at J. Gibson McIlvain, we carry a significant inventory of Ipe, including decking boards, joists, posts, and balusters. Whether or not you choose us as your Ipe decking lumber supplier, though, please consider our heart-felt request: whenever you’re sourcing Ipe for an exterior project, make sure to ask about kiln-dried decking. And then ask about the moisture content.