Is Wood Decking UV Resistant?
Wood is a common choice for deck stair railings in sunny, warm climates. The dry Yuma air, for example, helps prevent against wood rot, a major concern for the lifespan of a wood deck. It does have some drawbacks, though. Bare wood is easily damaged by UV exposure through a process called photochemical degradation, with UV starting to change the composition of wood in just a few days. UV light quickly damages the lignin in wood, causing it to lose its ability to keep its fibers bonded together. The result is a loss of pigment and a lessened ability to absorb stains.
If photochemical degradation occurs, the layer of weathered wood should be removed either by pressure washing or with a special deck cleaning solution. To delay or prevent it in the first place, you can use a semi-transparent or clear stain on the wood and finish with a UV-rated weatherproofing water-sealing product. Your wood will likely have to be cleaned and restained every 1-10 years, depending on what shade of pigment you choose to use and how well you maintain your railings.
Is Metal Affected by Sun Exposure?
Metal is a solid choice for deck railings in sunny climates—depending on the metal. Certain metals are more resistant to UV damage than others. Aluminum and the stainless steel in vertical cable railings, for instance, aren’t affected in any significant way by UV rays. Iron, on the other hand, does experience faint corrosive symptoms when exposed to UV radiation, but only if its wet. This is easily remedied by installing an iron railing system manufactured with a UV-resistant powder-coating that has a UV/corrosion resistant finish.
Powder coating protects metal from the elements—and adds a decorative appeal. Powder paint coating, compared to conventional painting, resists the effects of UV rays very well. Some companies even use a powder coat formula specifically resistant to UV radiation.
Vinyl Decking Material Options for Desert Climates
Vinyl and PVC are not recommended materials for your Yuma deck railings because of their tendency to chalk and discolor. The main ingredient in these products that impedes UV damage is titanium dioxide (TIO2). Low-quality PVC and vinyl railing products that are made with lesser amounts of TIO2 tend to fade, chalk, and discolor faster than other PVC based products with higher TIO2 content. But even quality products will eventually chalk and discolor, at which point they typically need to be replaced. It is possible to repaint them with oil-based paint, but this tends to defeat the purpose of installing low-maintenance fixtures in the first place.
It’s also possible for vinyl railings to expand and contract if temperatures fluctuate drastically. This is not a serious concern in Arizona, typically, but low-quality vinyl is more likely to separate at interlocking joints as it flexes and shrinks.
Glass Deck Railings Options
Glass could be a good choice for your deck because it doesn’t have any adverse reactions with UV rays. In fact, it actually screens UVB rays which typically cause sunburn. Balusters and panels made of glass can be installed with a variety of materials including metal, vinyl, wood, and composite railings. Full glass infills do not have balusters but instead have an entire pane of glass between posts with minimal spacing between the glass and the post. Due to their design, they don’t let much wind through and actually warm the space behind them by magnifying the heat.
If you like the aesthetic of glass but don’t care for its warming effects, as Yuma’s desert climate is often hot enough, opt for glass balusters, as they have spacing in between to allow for airflow. Be sure to install glass railings designed with a rail material like powder-coated aluminum or iron, as these are also low maintenance and are resistant to UV exposure.