Ipe is, without a doubt, the most popularly requested tropical decking lumber species that we sell. And we certainly understand why! Ipe boasts remarkable hardness and stability, along with unmatched weather resistance, allowing it to outlast any other decking species (or composite option). But that doesn’t mean that Ipe is without its challenges. When you know what to expect and how to work with its unique characteristics, though, you can install an Ipe deck that will last for decades.
Along with the remarkable hardness that Ipe boasts, this tropical decking hardwood species includes tough raised grain that is rough to the touch. This scenario is necessary, because in order to maximize the lumber’s stability and showcase its attractively consistent grain, Ipe decking is typically quartersawn. Quartersawn decking allows for exposure of the medullary rays, internal structures originally used to carry nutrients throughout the tree. These dense areas aren’t easily planed or smoothed out, so freshly milled quartersawn Ipe decking boards will require the use of a sander in order to achieve a smooth surface. Tropical hardwoods aren’t the only ones in which medullary rays are apparent, but the harder the species, the more noticeable the structures will be.
Because of Ipe’s exceptional stability, you might assume that it could never warp — but you would be incorrect. Any decking product will have a higher moisture content than lumber dried for interior use. Rather than being kiln dried, tropical decking boards dried for exterior use are simply air dried to a moisture range between 14 and 18%. Kiln-dried Ipe with a moisture content below 8% would be quite thirsty and prone to soaking up plenty of moisture when humidity or precipitation strikes; that drastic shift would cause extreme amounts of movement. The higher amount of moisture helps keep decking lumber stable by preventing extreme swings in moisture content and the kind of extreme movement that goes with it. But that doesn’t solve the problem entirely.
Because climates vary, an acclimatization period is important. Once your Ipe decking arrives on your job site, it should be given time to acclimate to its new surroundings for about 2-3 weeks. Ideally, it should be stored away from direct sunlight and stacked and stickered in order to allow for proper air flow. As the boards come into equilibrium with their new environment, they may expand by up to 1/4 inch. For that reason, allowing for acclimatization prior to installation is extremely key.
Following installation, it’s still important to reduce movement. One way to do this is to plan your deck with proper ventilation on the ground side. Another is to apply an end sealant (we recommend a wax-based coating such as AnchorSeal) to the cut ends of the boards; this application will help slow moisture absorption and loss as exterior moisture levels shift.
Continue reading with Part 2.