Do You Really Need Plus-Sized Decking?

The key to finding the best tropical hardwood decking for your project involves many considerations. Personal preferences will certainly come into play. But so should waste. And cost. And market realities. In the decking market, the 2 standard thicknesses are 3/4 inch and 1 inch (referred to as 1 inch and 5/4 inch). Thicker boards are understandably considered more stable and are often used in areas where the climate is extremely volatile or conditions are especially harsh. The extra thickness can help alleviate checking or cupping when temperatures swing. There is certainly a place for both thicknesses.

However, there is a third thickness, referred to as “plus-sized decking,” that is only slightly thicker than the ¾-inch material. Not only does the mere 2 mm difference in thickness provide negligible added stability, but this plus-sized decking also represents unnecessary waste and associated cost.

Why It’s Available

Saw mills are always looking for ways to market in-demand products to new markets. In Europe, the standard decking thickness is 21 mm — what we’re calling “plus-sized decking.”

Because of the higher levels of moisture throughout Europe, a thicker product is required. As South American mills are already producing this slightly thicker product for their European customers, they’re glad to offer it to U.S. suppliers, as well.

Like short lumber or odd-length decking, there’s nothing inherently right or wrong about decking thickness: To some degree, it’s a matter of preference.

How It’s Created

The issue arises, not due to the thickness itself, but due to how the 21 mm thickness is achieved. The mills typically start with the same rough stock used to create 5/4 material and simply plane more off. Even though the lower finished thickness allows more decking boards to be packed into a shipping container, the importer is still charged for the original volume (including the part that’s long gone via the dust collector).

Since the mill is getting the same amount of money but paying less for shipping, the benefit is to them. The customer, however, loses out by paying for the material attained as well as unnecessary waste.

Why It’s Unnecessary

In addition to the waste and suspicious motivations of the mills, we have another reason to discourage you from ordering plus-sized decking. Whatever species you’re installing, if the environment is hostile enough to warrant a thicker board width, why not go with the full 5/4 material? You’re paying for it, either way! Besides, it’s unlikely that an additional mere 2 mm thickness would make a big difference. (We won’t even carry thinner Cumaru than 5/4 anyway.) An additional motivation for avoiding this in-between thickness is that it’s uncommon enough in the U.S. to make finding more to fill in or repair an existing project quite a pain.

J. Gibson McIlvain Company

Since 1798, when Hugh McIlvain established a lumber business near Philadelphia, the McIlvain family has been immersed in the premium import and domestic lumber industry. With its headquarters located just outside of Baltimore, the J. Gibson McIlvain Company (www.mcilvain.com) is one of the largest U.S. importers of exotic woods.

As an active supporter of sustainable lumber practices, the J. Gibson McIlvain Company has provided fine lumber for notable projects throughout the world, including the White House, Capitol building, Supreme Court, and the Smithsonian museums.

Contact a representative at J. Gibson McIlvain today by calling (800) 638-9100.