By Rebecca Baum for Forever Redwood
Photographs courtesy of Forever Redwood
For hundreds of years, wood has been the favored material for pergolas, pavilions, and other outdoor shade structures. The five most common woods used in the U.S. and Canada for outdoor structures are California redwood, cedar, pine, teak, and pressure-treated wood.
Which type of wood is right for your project?
Your choice will determine the look, degree of maintenance, lifespan, and environmental impact of your structure. And of course, cost will factor in as well.
Let's look at the pros and cons of each of these woods.
Redwood (Sequoia sempervirens) was the outdoor wood of choice for most of the 20th century. But the redwood forests were over-harvested in the 1990s and lumber production collapsed to one-third the level of prior decades. Today, redwood is available only in California and a few western states.
A beautiful reddish-brown hue, it has an excellent reputation for outdoor durability because of its resistance to weather, decay, and insects. It's easy to work with, dimensionally stable, and accepts just about any stain.
Outdoor structures built from redwood can last 20 years or more in most climates with minimal upkeep. The more mature the redwood, the greater the longevity.
To minimize environmental impact, consider working with a company that sustainably sources from restored forestlands, like Forever Redwood.
Douglas fir (Pseudotsuga menziesii) is one of the more economical choices for an outdoor wood building material. Natural color ranges from blonde to reddish. Structurally, it's strong and demonstrates substantial decay resistance (though less than redwood). It’s ideal for drier climates, where a 20-year lifespan with little maintenance is possible. In wetter climates, resealing is recommended.
Teak (Tectona grandis) is a deciduous hardwood renowned for its elegance, durability, and longevity even under severe climate conditions.
Widely used in the U.S. and Canada, it's an economical choice for outdoor furniture and structures. It is typically golden brown, but can range from reddish to light yellow.
Environmentally, this wood is a mixed bag. Teak sold in the U.S. and Canada is 99% plantation grown, mostly in Central and South America. While this does take pressure off native forests, a significant percentage of these plantations are grown on lands that were once forests, often replacing native, biologically diverse lands with an imported monoculture that degrades wildlife habitat.
Of the six cedar species available in the U.S. and Canada, western redcedar (Thuja plicata) and Port Orford cedar (Chamaecyparis lawsoniana) work best for outdoor shade structures.
Western redcedar exhibits strong decay and insect resistance. It is lightweight, dimensionally stable, relatively strong, and has a beautiful grain that is easy to work with. Shade structures built from all-heartwood will last 15 years or more in most climates with minimal maintenance. The heartwood is a fragrant reddish-brown and the sapwood is almost white.
Port Orford cedar is a West Coast native of Oregon and California. It is relatively strong, highly decay-resistant, and reasonably priced.
Pressure-treated timbers are popular because they are inexpensive, long-lasting, and widely available. Average-quality pine lumber is processed chemically into a building material resistant to both decay and insects. This industrial wood product can last for several decades and, structurally, is relatively strong.
While pressure-treated pine works well for some installations, there are a few drawbacks. The toxic chemical process is not environmentally friendly. As well, the surface tends to dry out and develop splinters in a few years unless regularly maintained. Finally, the appearance is far inferior to that of teak, cedar, or redwood. The wood grain is punctured and unnatural in color making additional staining and finishing necessary.
Most pines (Pinus) have minimal natural insect or decay resistance. For example, southern yellow pine is beautiful, cost-effective, and readily available. But without constant refinishing and resealing, it will degrade within five to seven years, especially in moist climates. Pine fares better in dry climates if painted or treated with a high quality oil finish. But even then, much ongoing maintenance is needed.
To learn more important considerations for planning your shade structure project, visit Forever Redwood’s website or call (866) 332-2403.
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