Hot & Dry Climates (e.g. Desert Sun or High-UV Areas)
In very hot, dry regions (like the Southwest deserts or high-altitude sunny areas), sunlight and heat are the biggest enemies of a deck. The UV rays will bleach and break down wood fibers over time, and extreme dry heat can cause wood to dry out, shrink, and crack if not protected. If you want a wood deck in a climate with intense sun (think Phoenix, Las Vegas, or even the east side of Lake Tahoe which gets strong summer sun), consider woods that handle sun well and plan on using a good UV-blocking finish. Cedar and redwood do better than many others under UV because they don’t absorb as much heat and have those protective oils – plus, as noted, cedar stays cooler to the touch than denser woods or composites. They will still fade to gray relatively quickly if not stained with UV protection, however. Pressure-treated pine, if it dries out too much, can warp or develop large cracks/splits in prolonged heat. It’s critical to seal any wood in a dry climate to lock in natural oils and keep out excessive dryness.
One advantage of composites in hot climates is that they won’t crack or warp from drying out. They are more dimensionally stable in extreme heat. The trade-off is that composites can become very hot in direct sun – walking barefoot might be uncomfortable in the peak of summer. If you choose composite in a hot area, opt for a lighter color board, which will reflect more sunlight and stay a bit cooler, and perhaps design the deck with some shading (pergola or umbrella) for comfort. Tropical hardwoods like ipe handle dry heat structurally (they won’t warp) but being dark in color, they too will get quite hot underfoot. Some of the lighter tropical hardwoods (like teak or garapa) might be better in that regard. Also, high altitude sun (like in mountain areas) can be very intense on UV – expect to reapply finish annually if you have a wood deck exposed to high UV. Using a UV-protective stain or a pigment in the oil can greatly slow color fading and wood damage in sunny climates.
In dry climates, consider decking materials that are lighter in color (be it a lighter wood or a lighter composite) to reduce heat retention. Also, remember that even though the air is dry, if there’s an extreme temperature swing from day to night or between seasons, wood will expand and contract – so leave proper gaps between boards to accommodate that. If low maintenance is a must and barefoot comfort is secondary, composites or PVC decks are fine in the desert (some newer composites advertise cooler surface tech). If you love real wood in a desert climate, cedar might be one of the best choices for comfort (cooler surface), as long as you’re diligent with applying a good sealant to prevent it from drying out or discoloring too fast.
