Article No: 195
French Country in Oklahoma City
By: Carole McMichael
Concrete was the building material of choice for the owners of a more than 10,000-square-foot custom French Country mansion project in Oklahoma City. They saw the advantages of it in other homes constructed by their soon-to-be builder, Mike Hancock.
“They also liked the structural stability of it,” says Hancock, president of residential building company Hancock Building and Design and of Basement Contractors. “Because they were going to put money in the house and wanted to make it energy efficient, they saw that concrete was the best way to go.”
The three-story house boasts five spacious bedrooms, five full baths and two half-baths. The main floor rooms include: a master suite, which offers the special elegance of a domed ceiling; a living room; and a classic large French Country kitchen with a huge island, granite countertops and distinctive, hand-scraped distressed cabinetry and floors. The baths have radiant floor heating, while the rest of the house has oak, tile or carpet.
The full basement serves 21st-century needs with a well-stocked shop area (for him), a family room, access to an exterior swimming-pool area, a game room, ample storage spaces and two hobby rooms, (one for her and one for the kids). Also, there are two offices—one for the owner, a doctor who often does work at home, and another dedicated to family management tucked in close to the utility room.
The basement walls are 11 feet high; the main floor walls are 12 feet and the second-floor walls are 9 feet. Wall thickness varies as well. The second- and third-story concrete walls are 6 inches thick, but the basement walls are thicker for structural and thermal value.
Concrete usage extends to some of the interior details, too. The bar downstairs takes advantage of concrete’s decorative options in the countertops, and it was key to the design of two fireplace surrounds. The home owner showed Hancock some pictures of what she wanted; he carved them, made molds and poured the surrounds. “It was pretty, but very difficult,” says Hancock. “Actually, that was more of an art project.”
Cantilevered over the basement, concrete decks project 12 to 15 feet and are accessible by two staircases. One is a spiral staircase and one is a turn-back staircase supported by a column. It winds down to one landing, and then turns back under the deck. This approach avoids a visually obtrusive concrete structure, creating a minimal staircase.
The home’s impressive entrance is finished in stone, which harmonizes with the traditional French Country exterior of stucco and hand-molded aged brick. Several eyebrow windows add to the old European flavor of the design.
Hancock was raised in a family that “had a concrete company forever,” but decided not to follow that career and became instead a mechanical engineer. So, naturally, in spite of work in civil and structural engineering and project management, he returned to his roots in poured-wall construction.
“In Oklahoma City, there is a stereotype that you can’t put basements in here,” Hancock says, “so pouring walls in basements are a great way to teach people what can be done with concrete, and from there, they hear that I do concrete houses. I’d like to say it is because of the concrete, but it is my engineering degree that has more clout than anything. I can do the structural design work and I know building concrete houses. It’s like one-stop shopping that gives clients a real comfort level, knowing their house is going to be overseen by someone that has that background.
“In this general area, I’m the only poured-in-place guy in town with a set of forms. I have completed five houses in the last three years, and I’m in the middle of doing five more. If you are the guy doing concrete houses, you have a different client base than if you are just doing stick. In fact, my client base has grown more international. I have local clients that come from Nigeria, Italy and France.”
For his poured-in-place construction, Hancock uses the E-Maxx system, which fits inside forms from Wall-Ties and Forms and Precise Forms. He has worked with a variety of concrete systems, but prefers poured-in-place, because “it minimizes blowouts, keeps walls straighter and pours and sets faster. The system is readily available and established, easy to work with and more versatile—I don’t have to have polystyrene against the dirt if I don’t want it. It’s a simple method of pouring, and sets faster because of its size. With a 3-foot-by-8-foot panel, you set 24 square feet at a time and you’re done—and the forms can be stacked as high as you want.”
Ducks in a row
The upfront preparation for this project was key. Hancock had to complete the home in 18 months because the clients planned to host a wedding with 300 guests in gracious French Country style.
The owners came to Hancock first with ideas about what they wanted. They then took the plans to designer Don Hildebrand to complete and return to Hancock. Hancock made a few modifications to make sure the design was to his specifications and created the basement plan. The designer hadn’t designed a concrete home before, so Hancock reviewed with him elements like wall thickness, the locations of structural supports and construction techniques. No adjustments were needed for installation of the electrical and plumbing systems.
“Being the general contractor, the basement contractor and the engineer, I served a lot of roles in making sure the project was completed on time,” Hancock says. “Also, we had to get the subcontractors on board at the planning stage. There are always some glitches, but generally everybody complied with the schedule really well.
“The soil was solid sandstone, just as hard as it gets,” says Hancock. “It is good to build on, but it was a challenge to excavate. We did get into some iron rock and had a couple bounders that required two pieces of large machinery to move. We couldn’t work them into the house, but we did work them into the landscaping.”
The house sits on four residential lots, using the entire cul de sac. Hancock didn’t intentionally position the house for solar advantage, but it is well positioned anyway. Although the setting sun shines through the back of the house, 12-foot overhangs shade it from the fierce heat of the summer.
Concrete’s energy efficiency comes in part on the front end when the HVAC is purchased. Hancock ordered an energy evaluation that sized all the units to reflect the thermal advantage from poured-in-place construction. He ran a 90 percent efficient gas furnace (three units with a total of about 10 tons) with 14 SEER AC.
“The owners called one day to say the furnace wasn’t working,” Hancock remembers. “It was December 22. When I went over, I found they didn’t have the furnace turned on. It had been cold since October, but they hadn’t felt cold in the house until that time.”
How it’s done
“Once we got down to sandstone, we ran a 24-inch-wide and 12-inch-deep footing with three bars of 5/8-inch rebar,” Hancock says. “Then we put steel uprights in the footings and ran vertical and horizontal rebar, 18 inches on-center. The panels were locked together with a pin-and-wedge system. They are almost self-standing, but we braced them with walers. Then we used turnbuckles and kept the forms straightened out.
“We had the job foreman check before the pours, but I did some spot-checking myself. We poured one level up all the way around; then poured the floor and framed the basement. Next came the basement ceiling, and the stacking for the main floor. We finished one level at a time. Each level took a week. The pour was done in a day with just one pumper. It went very fast. We took the forms down the next day, and after that, we started to frame again. We had enough forms to do the whole project at once.
“I have 20 people who are used to doing poured-in-place that work for me. On this project, we had a pretty steady crew of 15 for the erection stage. With a house of this size, even a crew that big didn’t get in each other’s way.”
Hancock’s subcontractors are used to poured-in-place construction, but sometimes timing or budgetary issues force him to work with subcontractors who may not be familiar with the process. If there is a change, he has to train them in what he wants and how to do it.
“I hold classes for other builders as well,” Hancock says. “I do it usually twice a year, with 20 to 30 people in each class, so I get a lot of interest in terms of residential. They want to learn about poured walls and basements and concrete in general. Most have never worked with concrete and didn’t know it was a market. Now, they want to know why they aren’t in that market.
“What drives us in Oklahoma is tornados. If you are building stick houses and 500 get blown away in a tornado, suddenly concrete houses begin to look attractive to customers. For me, it’s basements that are driving things. They really bring builders into my classes. Basements give them the ability to build on land that they couldn’t have built on previously without having a tremendous amount of dirt work and retaining walls done. With a basement, they can save (rolling terrain is cheap land); and gain a building style that now makes it aesthetically pleasing and structurally stable to build a house down here. And you can market it to everybody in Oklahoma City who sees a basement as a haven from the storms.
“Many builders back away when they see the price differential to stick, but the key to that is education. With concrete, look at what you are getting for the dollar. If it is strictly just about price, there are cheaper ways to build than stick. If people are not looking at quality, it may be a tough market to sell to, but if they look at what customer base they are missing, then they will gain a lot.”
Hancock’s prediction for residential concrete construction is that more builders will specialize in production-style housing than in custom construction. He also predicts that a lot of poured-wall contractors will be building concrete homes from the basement on up.