Habitat homes form a concrete example

When construction professionals gather for Concrete Expo 2004 in Reno this week, they'll likely be talking about the growing use of insulating concrete form technology in new homes around the region.

The technology is being used everywhere from four Habitat for Humanity houses in Stead to upper-end residences in Mountreux, and its use is growing.

Here's how insulating concrete form ICF, for short building technology works: Lightweight polystyrene forms are stacked like building blocks to form exterior walls.

Steel reinforcing is placed in cavities in the forms, which then are filled with concrete.

After the concrete hardens, the foam forms are left behind to serve as insulation.

In other variations of the construction technique, foam panels or waffle-like grids are set with plastic ties to space them apart.

The space between the panels then is filled with concrete.

Frank Brock, whose Brock & Weigl Construction has built more than 200 homes using the ICF technology in the Reno-Tahoe area, said the system adds about 3 percent to the costs of building a home.

Because the ICF system replaces framing of exterior walls, framing costs are about 15 percent higher.

But the costs are offset by improved energy efficiency as well as lower maintenance costs.

"It's not hard to sell because it plays on common sense," Brock said last week.

"I love wood, but it's not the best thing to put between yourself and the elements."

The push for the new technology, however, is coming largely from consumers.

Builders, Brock said, are so busy meeting demand throughout northern Nevada that they're not interested in trying something new.

One of the consumers who pushed for use of the technology is Lorenz Robinson, who used ICF techniques for his dream home along Highway 28 on the eastern shore of Lake Tahoe.

The concrete-and-foam construction provides good sound insulation from traffic on the highway, which is just 30 yards away.

Robinson said studies show that concrete walls reduce sound transmission by more than two-thirds over frame construction.

And Robinson said he was attracted to the technology because studies found that ICF systems reduce energy consumption for heating by 44 percent and cooling by 32 percent.

Generally, Brock said, consumers who are interested in ICF systems in a new home are what he called "educated buyers" consumers looking to build a move-up home or buyers who have special needs.

ICF homes are popular, for instance, among buyers who are looking to live outside the traditional electric grid or buyers who are using solar in a new home.

At the same time, however, the technology is being used in the four starter homes built by Truckee Meadows Habitat for Humanity in Stead.

Because those homes are near the Reno-Stead Airport, noise insulation is particularly important.

The homes will be owned by families who otherwise couldn't purchase a house.

The Sierra Nevada Concrete Association is responsible for donation and funding of materials.

Volunteers build the houses under trained supervision, and donations help cover other costs.

Brock & Weigl Construction and the concrete association hope that the homes will help promote the use of concrete as a building material, Brock said.

Four years ago, they first used the ICF system in conjunction with Truckee Meadows Habitat for Humanity.

Concrete Expo 2004 will run from 8 a.m.

to 4 pm.Wednesday at the Lawlor Events Center on the campus of University of Nevada, Reno.

The fifth annual event will include presentations by Dr.

Ken Hover, a professor at Cornell University and a top technical expert on concrete.

He'll discuss methods to reduce cracking as well as techniques to improve the performance of concrete construction.