WHO COULD HAVE KNOWN THAT this year's 2005 New Urban Challenge (NUC) show home project, co-sponsored by Home and BUILDER magazines, would be wind tested so soon? The three homes, nearing completion in Baldwin Park, Fla., a savvy new mixed-use development, stood up to 110 mph winds this fall. But along with that testament of strength, they show off the latest and greatest in walkable, new urban community design.
Fortunately, the crews and trades who work with the project's builder, David Weekley Homes, in this area know how to accommodate the strict building standards without losing profitability. They were the right team to take on the job of building three adjacent homes for the project. And they have met every construction challenge, even the unusual ones—steep roof pitches and high stem walls—that occur when three homes are designed by three different architects.
“We stayed within the basic Florida building technique,” notes Randy Braiden, regional president of David Weekley Homes in Orlando, “[even though] we knew we were going to use some unusual sidings for the area, such as James Hardie's Hardiplank and Hardishake. Those products are much easier to apply over wood framing, but the market here is 90 percent block [concrete masonry units], so we decided to stay with that.”
Locked-Down Block The decision to build with concrete influenced construction on many aspects of the three two-story, 2,300-square-foot homes. For example, to attach fiber-cement siding to the first-story block walls, workers had to first attach wood furring strips to the block. To insulate the block on the interior, 1-inch foam “greenboard” panels were installed, followed by furring strips, prior to adding drywall.
“What they used to do in Florida was apply the foil-backed foam to interior walls,” Braiden points out. “But that foil has paper backing. Now, with concerns about mold, we've moved away from that product.”
Most homes in Florida are built slab on grade, but these architect-designed beauties called for higher block stem walls (above-grade sections of perimeter foundation) to raise the first floor of the homes by as much as 36 inches above grade.
In order to meet Florida code, says Braiden, the whole stem wall system had to integrate with the rest of the structure.
“What [Hurricane] Andrew taught us was that we need more strapping and vertical steel,” he notes. “Once we pour our footers, we put in our stem wall of block, with plenty of rebar. The top course of that wall is open on one side, just above grade, thanks to some special blocks. When you pour the slab, it ties in directly to the cement wall, so you end up with a monolithic base.”
Anchored to that base, Braiden says, are the concrete walls of the first story. But these, too, are carefully built so that the vertical cavities surrounding doors (including lintels) can be poured inside the wall to create a contiguous, super strong section of wall.
“We have our mason leave an opening in the block where the walls meet the slab for inspection,” Braiden explains. “Then, before the pour, he covers it up with some scrap wood.”
But the tie-down process doesn't end at the slab. In the top course of the first-floor block, masons bend over the rebar and attach it to a horizontal piece of steel, with straps that will support floor or roof trusses, depending on the design specifics. Ultimately, the entire building ends up firmly anchored into the ground. And prior to any construction, each new plan has to be approved by a certified Florida engineer. The end result: resistance to sustained winds of 110 mph.
Material Spikes Braiden says that since construction began on the NUC homes, material prices have shot up sharply.
“Concrete's gone from $60 a yard to $75 a yard. Oriented strand board has gone up 35 percent. Block is up 15 percent. But the biggest thing is that we're actually on allocation for our poured concrete in this area along with concrete block.”
That means that each builder in the Orlando area can purchase only a given amount of concrete or block per month.
“It's made us a lot more careful with how we use concrete,” Braiden says. “We can't start the number of homes we'd like to, so we've gone to even-flow production—which isn't necessarily a bad thing. And you better make sure you're absolutely ready to pour when an order is coming. That can be really difficult because this is our rainy season, so once the hole is dug, you want it poured right away. The swimming pool people are really backed up.”
“We really couldn't have picked a worse time for building,” Braiden continues, only half joking. “But the concrete companies are working really hard to accommodate us.”
Devil's Peak Ask some of the Hispanic roofers working on the NUC project what they think of the job, and they will point to the near-vertical roof pitch of the Cottage floor plan and say, “El Diablo.” That's the nickname they coined for the jutting peak, in an area where few roofs exceed a 6/12 pitch.
It's not like these workers are afraid to dance around at dangerous heights. After all, they have to be comfortable ducking and dodging in order to handle the big truss assemblies that are lowered into place by cranes, one after another.
“This has become the traditional way of building homes in Florida,” Braiden explains. “Our people have gotten very sophisticated at setting these trusses. I think it's a different skill set. People who might be good at conventional roofs are not necessarily good with truss systems and vice versa. But probably 95 percent of the homes in Florida are built this way.”
Wrapping Up With an exterior sealed with Tyvek house-wrap, carefully flashed and sealed window and door openings, low-E Pella windows, and foamed-in mechanical penetrations in the concrete walls, these homes should stand up to the Florida heat. The inclusion of 12- to 14-SEER air-conditioning units also should lower overall energy costs.
“We're lucky to be building in one of the nicest places in the state,” says Braiden, “and we're doing it with a variety of designs and materials.”
Learn more about markets featured in this article: Orlando, FL.