Decking Decisions

There's just no doubt about it ... high quality decking is a definite must for a high-quality, elegant landscape project.  The decking shown here is an "outside room" at the rear of a Philadelphia townhouse.

According to US Forest Service botanist Alex Wiedenhoeft, an expert in tropical wood species, one of the most popular materials used in decking today is ipe.  Ipe is a very strong and durable tropical hardwood imported from Brazil, touted for its resistance to rot, decay, insects and mold.

Wiedenhoeft says that ipe is "as decay resistant as everyone claims," but he warns that the wood is often brought into the US green, and it's then processed and installed before it's properly dried. "Ipe is much more likely to fail as a deck because the material shrinks, causing cracks, splits, and cups," he says.

Another popular tropical species is meranti, also known as Philippine mahogany. This comes from the genus Shorea, of which there are some 400 species, not all suitable for decking.  Shorea is generally categorized into five groups: white, yellow, light red and dark red merantis, and balau.  Wiedenhoeft says only the dark red merantis and balau should be considered for decking because the other groups of shorea "do not have sufficient natural durability for decking applications."

So, designers, be sure you're using the right material -- and then beware the problems that could arise.  Perhaps the old standbys of redwood and cedar would do the job just as well.