If you want to understand Black Locust decking — really understand it, beyond the spec sheets and the marketing — the best thing you can do is listen to someone who has spent a decade in the weeds with it. Zach Rike, founder of Robi Decking, recently joined Harry Greene on the Plant The Trees podcast for a 58-minute conversation that covered everything from how Robi got started, to why tropical hardwoods are running out, to what actually went wrong with the Squibb Park Bridge in Brooklyn.
It’s one of the most honest and informative conversations about outdoor wood products we’ve heard. Here are the highlights — and a link to listen to the full episode.
How It Started: A Porch, a Lot of Research, and a Gap in the Market
Zach didn’t set out to build a decking company. He was putting a screened-in porch on his house in Atlanta in 2015 and started researching his options.
“I knew that pressure-treated pine was not something I wanted to use. I’ve had a lot of experience with wood. My dad was in a demolition business, and I’ve been around wood since I was a little kid reclaiming lumber, and I’ve seen the degradation of pressure-treated pine over the last 20 years.”
Softwoods were too soft. Composites weren’t for him. Tropical hardwoods like Ipe were interesting but raised questions. So he asked a different question entirely.
“I started thinking to myself, there has got to be some type of wood species right here that grows that is naturally rot resistant. Because we’ve built boats out of wood for hundreds of years here.”
That question led him to Black Locust — and then to hundreds of hours of research, a deck he built himself, and the realization that nobody had really productized it for the modern market.
“The potential customers and customers I would talk to were extremely interested in the wood. They were in the same position as me. They wanted a wood deck, they did not want pressure-treated, they did not want a softwood, they did not want the tropical hardwoods, they did not want a plastic deck, they wanted a natural hardwood — but there were no options on the market.”
The Tropical Hardwood Problem — In Zach’s Own Words
One of the most compelling parts of the conversation is Zach’s breakdown of what’s happening with tropical hardwoods — a topic we’ve covered in depth in our post on the CITES listing of Ipe and Cumaru. Zach has been watching this closely since he first started researching the market over a decade ago.
“The tree that Brazil was named after — the Pernambuco tree — was heavily exported by the Portuguese. That tree no longer exists. No one can get that tree to grow. If you look at teak — not the plantation-grown teak, but the forested teak that’s really rot resistant — that’s pretty much gone. Big leaf mahogany is pretty much gone.”
On Ipe specifically, Zach shared a striking statistic from a British research report:
“Some researchers went into the Amazon and actually carbon-dated trees — because no one had done that before, because they don’t have growth rings, so you can’t just count the rings. What they found was astonishing. The average four-inch diameter tree was on average 350 years old. And when you consider that we are cutting down some of these Ipe trees that are six, eight feet in diameter — these trees are thousands of years old.”
He’s also frustrated by how slowly the industry is responding:
“It befuddles me every time, because we go to a lot of the conferences — the ASLA conferences and whatnot — it’s still amazing to me how many people still use Ipe and the tropical hardwoods, even with all this knowledge that we have today. And we’ve got great alternatives that we’re not using nearly as much of.”
The Home Depot Story: Planned Obsolescence, Explained
This might be the most memorable moment in the entire episode. At the 2019 Green Build Conference in Atlanta, Robi had a 10×10 booth diagonally across from Home Depot’s enormous presence. After a long day, the national head of decking for Home Depot wandered over. Zach asked him a direct question.
“We get a lot of calls weekly from folks that put in a pressure-treated deck five years ago, ten years ago, and they’ve got to replace it. All that money spent on the deck — and the biggest expense is not the wood, it’s the labor and the tools and the screws and all that, and all that’s wasted when your deck is rotted out after five years. I said, why do you still sell this pressure-treated pine decking?”
The answer was two words.
“He had a big smile on his face with a big glass of red wine, and he said two words: ‘Repeat customer.'”
“That’s not the way I ever want to operate a company. I want to sell a product that I use myself, that I stand behind, that I’d be happy to have my kids stand on, my wife stand on, my dog running on. And never in my life would I sell a product like that.”
Working With Black Locust: What Contractors Need to Know
Zach is candid about the fact that Black Locust requires more care than pressure-treated pine — and equally candid about why that’s worth it.
“A lot of folks are not used to building with hardwoods like they were a few generations ago. The biggest thing you have to explain is really two things. Number one, you have to pre-drill the wood. And the second thing is being creative with working with the shorter lengths — because they’re not all uniform eight-foot, ten-foot, twelve-foot, twenty-foot lengths.”
But the end result consistently surprises contractors who’ve never worked with it before:
“We have never had a customer complain that once they’ve installed their deck, you just don’t care if it’s got some three-foot and four-foot boards and it’s random length. It actually makes it look cool. It showcases the natural wood and the differences in the grain from board to board and the differences of color.”
On kiln drying — a topic Zach feels strongly about:
“For decking and siding products, it is absolutely critical that the wood be kiln dried. Every region in the United States has an equilibrium moisture content published by the USDA. We dry our decking and siding products down to 12%, which covers about 95 to 98% of the United States.”
The Squibb Park Bridge — The Real Story
The Brooklyn bridge that’s sometimes cited as evidence that Black Locust fails comes up in the episode. We’ve addressed this in our Pros & Cons post, but Zach gives the most detailed account we’ve heard of what actually happened.
“What they did was use Black Locust logs that they peeled, and they encapsulated the ends of those logs in metal connectors — think of a cigar in a cigar holder. As the wood expanded and contracted through Brooklyn’s seasons, it basically pulled those holders apart.”
“Wood is not soft tissue. It’s an extremely hard, dense material. When it expands, it’s got to expand into something — and it expanded into those metal holders and basically broke them apart.”
He had the analysis confirmed by an expert who builds wood bridges professionally:
“I showed it to him, and he was just like, what were these people thinking? They were going for a design look. They did not understand the means and methods of the material.”
His broader point is about the whole project delivery chain:
“You’ve got to have an owner who’s on top of things, an architect who understands the means and methods of the materials they’re using, an experienced builder who understands the physics of the material, and you’ve got to choose the right building products from the right suppliers. If one or multiple things in that chain fail, you’re going to have a problem with your project.”
Products You Might Not Have Thought Of
Two product lines came up in the conversation worth highlighting. First, deck tiles. Because Black Locust trees don’t yield long boards, a significant amount of material comes off the mill as shorter strips. Rather than treat this as waste, Robi mills them into two-by-two and two-by-four deck tiles — a product that has taken off particularly in New York, Chicago, and other cities where rooftop outdoor spaces are in demand.
Second, end-grain wood pavers — with a remarkable backstory. Robi received requests from both the City of Cleveland and the City of Philadelphia to replace cobblestone streets made from Black Locust in-grain pavers, some dated back to 1888 — meaning the original pavers had lasted over 130 years. Robi now produces these as a permeable paving product that helps manage stormwater and reduces the urban heat island effect.
“Before the advent of concrete in the early industrial revolution, factories and warehouses would turn the wood up on the end grain, and that would be the floor of the factory. The wood would be self-treated with dirt and grime and oil from machines that would actually help preserve it.”
The Bottom Line — In Zach’s Words
Zach closed the episode with an observation about where the building industry has gone — and where he thinks it should be going:
“Using natural products in general, I think, is a better way to build. And that’s not the way the building industry is going right now. Using stone and metal and glass and wood and brick — using more natural building materials — is being replaced by synthetic products that are fast and easy and cheap to install. And there’s just a degradation in the building of houses that’s going on now.”
“For folks that want a high-end deck or a high-end siding product — I think we’ve got a great product. And folks are going to enjoy their outdoor living space for a very long time with really minimal maintenance.”
Listen to the full episode on Spotify or Apple Podcasts. It’s 58 minutes well spent if you’re serious about outdoor wood products, sustainable building, or the future of the hardwood market. And check out Propagate — Harry Greene’s agroforestry company and the home of the Plant The Trees podcast.
→ Browse Black Locust Products at robidecking.com
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