Concrete Solid in Southampton
By: Carole McMichael
Photography courtesy of Nicolas Alimanestianu
Southampton Building Corp.
Insulating concrete forms (ICFs), whether blocks or panels, have been around for several years—long enough for the industry to develop a number of systems. ICFs are differentiated by the design of the forms, type of materials for ties and style of connections. What most have in common is the basic configuration: a concrete core, which is strengthened with rebar, sandwiched between polystyrene foam forms. More recently, as the demand for concrete housing has grown, other options have come on the market. One in particular is a kind of reverse ICF, developed by EVG of Austria and manufactured in this country by ICS 3-D Panel Works, Inc.
The 3-D Panel is composed of a modified expanded polystyrene core sandwiched between two outer layers of 2-inch-by-2-inch reinforced heavy-gauge wire mesh. Galvanized truss wires pierce the core and are welded to the outer mesh layers, structurally supporting the panel. The outer wire mesh is then coated with shotcrete on either side.
The polystyrene core ranges in thickness from 2 inches to 8 inches. The insulating factor is somewhere around 6 per inch—a 4-inch core would produce an R-value of 24. Standard panels, which are erected vertically, are 4 feet wide and 20 feet long, but can be ordered up to 40 feet in length. They are manufactured to specific tolerances, with rebar rods embedded in the polystyrene, then welded to the outer grid. The panels can be precut for the builder or they can be cut in the field. Because the system uses a wire mesh, a circular saw can cut through the panel easily. The beauty of this system is that builders can cut arches or circles for windows right on site.
Nicolas Alimanestianu, president and owner of Nicolas Alimanestianu Southampton Building Corp., is one of the concrete home enthusiasts who have chosen to build with the 3-D Panel system.
“When the panels for this system are erected,” Alimanestianu says, “they are tied together with wire mesh and ties. Next, we burn little channels into the polystyrene, put in the electrical conduit—switches and outlet boxes—and any other low voltage we want, and water pipes. Of course, we cut all the openings for doors and windows, as well. Although the panels are self-supporting, they need to be braced to level them and keep them all aligned. Then we check everything and spray the concrete.
“The mix we use has a psi of 3,000. It is premixed concrete with fiberglass fiber to add reinforcing and a very low grit. It is put in a big silo, dropped into the mixer and sprayed on the mesh. It can be just a two-step process, but I use a three-step. The bracing is removed after the first spray, then we do the second spray. The third step is the stucco finish, but we wait on that until the house is completely done.
Alimanestianu, trained as a civil engineer, has worked in different parts of the world, but has always been involved with construction. He moved to Southampton, N.Y., in 1984 and established a business focused on residential design, renovation, restoration and construction. In the early 1990s, after building in an area dealing with constant humidity, lots of termites and peeling paint, he began looking for something that would stand up to the elements, rot, and general maintenance problems. In 1994, while working with a company constructing gunite pools, he was introduced to a system that was being used in the Caribbean to withstand hurricanes. That eventually led him to the 3-D Panel system.
The advantages of using the 3-D system, from the builder’s point of view, are that the lightweight panels lower shipping costs and make onsite handling easier for the crew, which also speeds up erection time. That, in turn, can lower labor costs. Additionally, the builder is erecting the entire structure—ceilings and floors—out of one system.
The advantages from the customer’s point of view are tied to the finished product, which is what sells a house: no termites, no rot, no settling and very low maintenance. In addition, the fire rating is higher than any client will ever need. A demonstration in which a cottage built using 3-D Panels was subjected to a wildfire and survived upheld the fire protection claims.
“I like the solidity and permanence of concrete housing,” Alimanestianu says. “I like to build something that is going to stay.”
“Building with the 3-D Panels was not the challenge,” Alimanestianu says. “Finding a crew was. There are not that many men who are qualified to work with concrete in this area, or the ones who are, are busy. The spraying itself is labor-intensive. You need to have a lot of men—two on the mixer, two on the hose, and depending on the size of the building, you may need four men following the sprayers to level the concrete. Spraying is also a messy job, so you have to be very careful that you keep everything clean where you are working.
“My first 3-D Panel project was my office/residence building. It took a long time, but we were working as I had men available. It was a hard learning process for some of the crew, who were made up partly of guys who do gunite swimming pools and were used to spraying concrete, and partly those who were not. The gunite guys were happy, but the carpenters were complaining at first. I can still say I had a very good crew.”
Alimanestianu also found working with some of the subcontractors difficult, and ended up completing some of the installation himself. The inspectors were also uncomfortable with the unfamiliar system, but had to approve it because it all met code. Even getting building permits required going the extra mile with specs and background on the system’s technology.
The Stone house
The 4,500-square-foot hilltop home, built for nonfiction writer Michael Stone, sits on 5 acres in the heart of the Southampton hamlet of Water Mill. From the roof, Stone can enjoy spectacular views of the ocean and the bay. The Mediterranean-style villa, which serves as a weekend retreat for the Manhattan resident, has three floors and a walkout basement with two bedrooms on the walkout side and a full basement opposite.
The entire house, including the basement, is built using the 3-D Panel system, as well as the stairs, inside and out. On the main floor, a large central living room has a guest bedroom at one end and the dining room and kitchen at the other. Upstairs, there is a grand, two-story library and a tower. The spacious master suite, with a large dressing room and master bath, completes the second floor.
Stone chose polished concrete floors throughout the residence. They are stained with an acid-washed finish, mostly in browns, but the stairs are stained green. The countertops, also concrete, have a finish similar to the stairs. Stone also chose hydronic radiant heat, a perfect partner for concrete flooring. It is installed throughout the house, including in the basement bedrooms.
“Hot air heat was also installed because radiant can take a whole day to heat up the concrete once it gets cold,” Alimanestianu says. “But, so far, Stone hasn’t had to turn it on. In fact, when he gets to the house, he opens the windows because the radiant system heats the house so well.”
The most unusual feature of the home is the mahogany Jacuzzi on the roof deck. There is a 3-foot railing wall all the way around the flat roof, which has a pitch for draining. Holes in the wall allow rainwater to go into copper leaders. Another unusual feature is the barbecue made from 3-D Panels. With the gazebo, it anchors the outdoor dining and entertainment area.
How to do it
The 3-foot-deep, poured-in-place footings include protruding rebar to which the panels tie as they are stacked vertically. The floor and ceiling panels are erected at the same time, braced mostly with two-by-fours, but also with some adjustable bracing and lally (steel) columns. The ceiling panels are tied to the wall panels with wire mesh. Then the wiring and conduit is installed, as well as some ducts for the heating. Then the panels are sprayed. The basement floor is poured after the basement walls and ceiling.
The thickness of the ceiling panels in the Stone home was 8 inches, total. Alimanestianu waited a week for a pour to cure part way, enough to continue the erection process. (Maximum strength would take 28 days.) The construction process was the same for the main level on up. The walls were 12 feet on the exterior, 11 feet on the interior. On the second floor, they were 9 or 10 feet. The windows, which open inward, were installed European fashion, flush with the inside wall.
Generally, the first coat of shotcrete sprayed on three or four 20-foot walls, 12 feet high, takes two to three days. As the coating dries quickly, the second coat can be applied directly afterward, but will take a few more days to dry. The first coat does not require leveling, but the second requires three or four crewmembers to level it immediately.
“The shotcrete is pumped from a lift with a 40-foot extension,” Alimanestianu says. “However, the stucco crew uses a scaffolding.” Stucco—Alimanestianu prefers true stucco to synthetic—can be applied in a week, but so it isn’t damaged during construction the crew waits until everything else is completed. Alimanestianu says his crew can complete one side of a house in a day, so they don’t stop mid-wall, which could leave marks. The stucco crew requires eight or 10 men, so Alimanestianu uses his own men in addition to four or five extra workers.
Alimanestianu’s crew added color, a simple beige, to the stucco of the Stone house. The color is uneven, adding to the home’s Old World look. Any color within reason may be created, depending on the color of the original stucco. Various grits can give stucco a sanded finish, and polishing can produce a very smooth finish. The Stone home’s exterior has a wavy, rustic finish, further complementing its aesthetic appeal.
Educating the public
Alimanestianu says that whenever he’s been directly involved in design, he’s been able to convince clients that concrete is the way to build. “As far as the future for the 3-D Panel system in the residential market is concerned, if we educate the public, I think it will take off,” he says. “But there is a learning curve. I don’t know how long that will take. If we have a hurricane, maybe they will see the advantages.”
For more information, visit southamptonbuilding.com