Wood Vs. Plastic: Building A Deck That Lasts

“In all things of nature there is something of the marvelous.” — Aristotle

Most people living on the East End appreciate the beauty of the natural landscape that surrounds us. In many cases, that serene beauty is a primary reason for living here, choosing to shun the complexities and abstract shapes of a crowded, man-made world for the calm that comes from nature’s simplicity and the harmony of its components.

One of the ways many of us enjoy the natural setting around us in the Hamptons is from the vantage point of our own backyards, and in many of those backyards, a main component of the beauty and functionality of the environment is the deck.

Almost every house in the Hamptons has a wood deck of some kind, and some have more than one. Some are utilitarian, serving as stairs or boardwalks, while others provide space upon which we enjoy good friends and good times as the evolving seasons display their ever-changing magnificence around us.

But, like anything else, if you want your deck to continue to provide you with good service, it’s going to require occasional maintenance.

For some people, the thought of any maintenance at all is distasteful. With the busy lives most of us lead these days, it becomes a matter of time management as well as expense. So people naturally look for decking solutions that require minimum or — even though it is nonexistent — “no maintenance.” Some even consider utilizing unnatural, man-made plastic materials to try to achieve this, thereby trading off the warmth and beauty of a natural wood environment for an artificial and toxic one.

Fortunately, with proper planning and choice of species, a deck built of wood can provide excellent performance and minimal upkeep, while maintaining as natural an environment as possible.

Call me a snob if you like (I much prefer the terms “woke” and “purist”), but I’m partial to the use of wood over plastic or composite materials for residential decking, the reasons being both aesthetic and environmental.

When I first started building “sun decks” in the late 1960s and early 1970s, redwood was the material of choice for construction. Originally part of the West Coast modernist architecture boom of the ’50s and ’60s, redwood for residential decking and siding was common and plentiful and not particularly expensive. Along with western cedar, it suited the designs of contemporary homes built into wooded mountainsides and offered the natural preservative aspects required to withstand exposure to the elements.

This was also before the popularization of chemically infused “pressure treated” lumber, so the entire structure, including framing, was made of redwood or western cedar as well.

During the ’70s, southern yellow pine infused with copper, chromium and arsenic (CCA) became very popular for use in backyard decks and was promoted as a maintenance-free option for decking, which allegedly no longer required annual or regular maintenance.

Although the chemicals used to preserve the wood in today’s process of pressure treating are less toxic than originally employed in modern times, most pressure-treated wood these days is used only in the substructure of the deck, except in circumstances where its properties lend it to superior performance, like marine and commercial environments. (An interesting fact is that treated lumber has been around since the Roman Empire used olive oil to preserve bridge support posts, and tar to preserve the hulls of ships.)

Another quality of pressure-treated lumber is the fact that it tends to “check” and warp as it ages, and the infused chemicals evaporate from within, making it unsightly and undesirable for use as a deck surface. However, as I mentioned, its positive properties still make it the material of choice for deck substructures.

As the old-growth redwood and cedar forests of the Northwest became depleted, modern, sustainable foresting began to take hold, and most of today’s choices of wood decking are grown and harvested in an environmentally correct way.

These days, in our East End environment, most wood decks are constructed of cedar, mahogany or more exotic tropical hardwoods like cumaru and ipe — Brazilian teak and Brazilian walnut, respectively. Each of the species has its own nature and unique properties, and depending upon the application there is one for every project.

How long milled wood will last in exterior environments depends largely upon the density of the wood and the conditions it must endure. In general, the harder or more dense the wood, the longer it will last. That density factor is also what differentiates a softwood from a hardwood.

To accurately rate the various density of different wood species, a rating system called a Janka (Yank-a) scale is used. The Janka test measures the amount of force required to embed a 0.444-inch steel ball into the wood to half of its diameter. The higher the rating, the more dense the wood is.

In the case of the popular deck woods mentioned above, cedar has a Janka rating of around 350, while Philippine mahogany rates at 800, cumaru at 3,300, and ipe at 3,600.

Where cedar and mahogany will require at least minimal maintenance of cleaning and coating with a clear preservative every few years, the cumaru and ipe will last up to 50 years or more with no maintenance at all.

Where a deck is located, its elevation and installation method also come into play as to how long a deck material will last. Drainage and airflow are of paramount importance to deck lifespans.

Decks that receive little or no sun, yet are exposed to moisture from rain and snow, will tend to stay moist and develop mold and rot over time if left unmaintained. Decks that are close to the ground are more susceptible to rot from continued exposure to moisture evaporating from the ground and minimal airflow. And if the spacing of the boards is too narrow when installed, spaces will clog easily with organic debris, interfering with drainage and proper airflow, which will shorten the lifespan of a deck.

Also, today, there are fastening systems available that virtually eliminate the use of screws or nails into the deck surface, eliminating unsightly fastener heads where water penetrates the wood, thereby improving longevity and improving aesthetic appeal and comfortability of use.

Our natural world is under assault from the proliferation of plastic and other man-made products that don’t decompose and pollute our natural resources. Towns and villages are banning the use of plastic products like straws and foam containers to help save our environment for future generations of all life on earth, not just human.

Not only are many of the man-made decking options not environmentally friendly, they’re not really “maintenance free” either. PVC plastic and composites are susceptible to mold and discoloration. Composite decking has been found to contain harmful chemicals and cannot be refurbished.

Why would we promote the use of plastic, non-sustainable, toxic products when a beautiful, natural option exists at a comparable or more reasonable cost?

By understanding the nature of the wood species and the reality of site conditions, one can choose the proper material for the project and facilitate a long life for your deck with minimal concern for its longevity, while being in harmony with nature.

Aristotle would approve.

Richard M. Kostura is the owner of Dick’s Decks of the Hamptons, a division of Heather Dunn & Co. located in East Hampton.