North Carolina Builder, By Susan Brimo-Cox
Discard all your old perceptions and mental images about concrete block homes. No longer are they the undistinguished boxes we remember from years past. Today they are used to create beautiful homes. But you’re not likely to recognize one- they’re that nice looking.
Of course, your chances of seeing a concrete masonry home dramatically increase if your travel to Florida. Unlike the rest of the country where wood is the primary framing material, in the Sunshine State concrete block is the preferred material. That’s one of the places North Carolina builder Rex Bost saw and grew to appreciate the many benefits concrete masonry has to offer.
“I’ve always been intrigued with this type of construction. I’ve seen it in Florida, out west and in the Third World. In North Carolina, we live in a softwood region, but I wanted to build a concrete masonry home,” explains Bost, president of Bost Construction Co. in Cary.
Bost grew up as a mason. “My dad was a masonry contractor. I laid block and brick through high school and college. And I had a stone masonry company for several years before getting into building,” he says. With his understanding of the many positives of concrete masonry, it was just a matter of time until he began the project, which he did in 1999. Bost built the house as a spec home for the Triangle’s Parade of Homes. It was a big house- with some 7,000-square-feet of living area- and was soon dubbed “The Rock.”
BUILDING WITH BLOCKS
The Rock took nine months to complete, from groundbreaking to completion. Bost says, “It was slow getting out of the ground, but we made up the time.” With assistance from the Johnson Concrete Co. and the Carolinas Concrete Masonry Association, he developed some creative approaches to combine masonry walls with wood-framed doors and roofs.
Bost built the home in layers. “Instead of standing up the shell and then framing the interior, we erected the house floor by floor- foundation, first-floor walls, then second-floor walls,” Bost explains. In between the masonry work on each level, the framers came in and did their work. “I had special concerns with scheduling.” But it all worked out, Bost happily remarks.
Bost handled insulation differently too. “The cores of the block walls were filled with concrete and, in some places, with expanding foam insulation. Walls on the inside were also framed with batt insulation.” This provided for high-efficiency walls with virtually twice the insulation.
On the exterior, Bost applied real stucco. Of course, his options were pretty wide open. Brick, natural or manufactured stone, architectural masonry, fiber-cement siding and more work exceptionally well over concrete masonry. Inside, wood strips supported sheet rock and created a cavity for the wiring, plumbing and interior insulation. Inside and out, The Rock looks like any other traditionally built home.
Structurally, concrete masonry homes offer protection from fire, termites and rot. They resist wind load and perform well in hurricanes and tornadoes. “With our recent history of violent weather, unstable lumber prices and exterior cladding failures, [concrete masonry] just makes good sense,” Bost points out. They are also low maintenance, quiet and energy efficient. “Concrete framing absorbs heat and retains it, emitting it over time. This allows a home to heat and cool at off-peak hours- an additional benefit beyond R-value.”
How much did it cost to build The Rock? Bost says, not including the lot or commissions, the total tab was around $1 million. “It cost about 4 percent more than a similar, conventionally constructed home with brick veneer.”
Well, The Rock didn’t sit on the for-sale block (pun intended) for long. It was purchased two months before the Parade of Homes- when it was only 70 percent complete and at the sheet rock stage. Dan Miller, owner of The Rock, wasn’t a stranger to Rex Bost’s products, however, “The Rock” is his second Rex Bost home. And he is delighted with it.
“Except in Florida, I’ve never seen this type of construction before. I have solid, 8-inch concrete block walls to the third floor. I don’t have to worry about termites,” and it’s quiet, too, Miller says. “We get overhead air traffic for Raleigh-Durham Airport and railroad tracks nearby. Inside the house, we can barely hear them.”
Miller says the home’s energy efficiency is significant. In his former 3,700 square-foot home, his air conditioning bill was approximately $275 a month. In the 7,000 square-foot masonry home his air conditioning bills run from $450 to $490 a month. That’s twice the house at 75 percent of his old home’s cooling cost per square foot. Energy efficiency in the heating season is similar, he says.
Miller reports he saves on his homeowner’s insurance, too, on potential damage from fire, falling trees and the like.
Now, two years after moving in, Miller observes, “It’s hard to describe any differences [from other construction] when I’m living in this house- it doesn’t live any differently than traditionally constructed homes.” But he knows what his home is made of and, that, makes him feel so much better.