Types of Decks
Sorting Out Treated, Cedar, and Exotic Woods From Manmade Materials
Should you use pressure-treated, cedar, or exotic wood for your deck? Plastic or composite? Here are the pros and cons of the different options
Building a deck is one of the most rewarding home improvement projects going. What else can add hundreds of square feet of living space to your home for only a few thousand dollars? And any reasonably handy DIYer with a working knowledge of local code requirements can build their own. But whether you build it yourself or hire someone to do it the first decision you face is, what material do you want it made of?
Pressure-treated
Greenish hued pressure-treated (PT) lumber is one of the most commonly used materials for decks, fences, and other outdoor building projects. It’s popular for three reasons: It’s durable, it’s cheap, and it’s widely available.
In fact, homeowners looking to trim down the budget on a higher end deck will commonly use PT wood for the structural framing and cover it up with cedar or other decking and trim.
With long-standing consumer fears that arsenic could leach out of the old copper chromated arsenate (CCA) treatment, the PT industry has changed the formulation to ACQ and TK. The new mixtures are more corrosive to fasteners than CCA was so be sure you look for screws and bolts labeled “ACQ approved.”
Cedar
Cedar’s popular because it’s attractive, easy to work with, and is naturally rot- and insect-resistant. Unfinished, over time cedar will turn a silvery grey colour and last about 10 years. You can double that, and retain its golden hue with regular applications of stain or waterproofing.
The main drawback is price as cedar costs roughly twice as much as PT.
Exotic wood
There are a number of so-called “exotic” lumber species that are used on high-end deck projects, including ipe, mahogany, cambara, and Tiger Deck, the brand name for a Latin American relative of the cashew tree. They’re all durable, with natural rot and pest-resistant characteristics but people choose them for that “one of a kind” look. The biggest downside is that exotic lumber can cost three times as much or more than PT wood.
Composite
Composites are made from a combination of wood fibres and recycled plastic. Trex is the most recognizable brand name, but there are several others on the market, including Brite, TimberTech, and CorrectDeck. You cut and drill composites much like you would real wood, but they don’t have any of the knotholes or checking that comes with natural lumber. They’re available in a variety of colours (including matching railings) and come with warranties of up to 25 years.
On the downside, while the boards themselves are quite heavy, they can’t be used for load-bearing members. (As with cedar, PT framing is often used under composite cladding.)
Like exotics, composites are about three times the price of PT lumber, and may also require pricey fastening systems.
Plastic/PVC
The deck boards and railings sold under brand names such as Eon, Perma-Deck, and Plasboard are made entirely of PVC (either new or recycled). They have most of the same pros (variety of colours, matching railings, long warranties) and cons (high price) as composites. If you opt for non-wood decking, your choice really comes down to which product you prefer the looks and feel of.
