Natural wood has been the decking material of choice in Montana, but if you're planning on "greening up" your house, there are some terrific looking and sustainable alternative materials.

Wood-plastic composite lumber incorporates some of the characteristics of wood with those of plastic lumber. Recycled plastic resin (usually polyethylene) is combined with wood or another plant fiber - which may be post-industrial recycled content or virgin fiber - to create a product that has various advantages over both solid wood and solid plastic. Like plastic lumber, it will not rot, crack, or splinter, while the wood fiber adds considerable strength. Wood-plastic composite materials generally have a more natural coloring and appearance than 100%-plastic materials. The wood fibers, however, may absorb water and fade in color over time. Brands include: MoistureShield, ChoiceDek, CorrectDeck, WeatherBest Decking, Rhino Deck, EverGrain, and the best selling Trex.

In 2003, the EPA estimated that 26.7 million tons of the municipal U.S. solid waste stream was plastics. Just 1.4 million tons of it was recycled; the rest went to landfills, where it occupies about 25% of the overall landfill space. Plastic lumber makes good use of recycled plastic and is an effective replacement for pressure-treated lumber, protecting timber resources and preventing the use of chemical lumber treatments. Plastic lumber won't rot, absorb water, splinter, or crack; it's also resilient to shock, making it an extremely durable component in exterior and marine applications. It can accept most types of fasteners and is workable with standard saws and carbide blades. Brands include Verdura and Perma-deck.