Colleen Mentz has managed about 400 home construction projects over the last 20 years. So, it’s easy to imagine her surprise when a 1,546-square-foot, three-bedroom single-family home recently finished two months ahead of schedule.
“From breaking ground through putting the roof on, we saved about two months overall. Excavation to roof installation took less than five weeks,” Mentz reports, adding the work in an historic landmark district “… slowed us down a bit.”
Construction speed was just one of the pleasant surprises for this Habitat for Humanity - Denver project in the storied Curtis Park neighborhood. Mentz is the Denver chapter’s construction manager.
Big Eye Opener
The difference-maker for this build? The home is constructed with insulated concrete form (ICF). ICF is a highly evolved wall system formed by stacking foam-framed blocks Lego-like to create a steel-reinforced, cast-in-place concrete wall. The Curtis Park home is Mentz’s first ICF project. It was an eye-opener. “It went up fast compared to a typical project,” Mentz says. “The trades were in there much faster than normal.”
Mentz’s chapter colleague, Chelsey Hume, AIA, real estate development project manager and the project designer, says her first-time ICF experience was fun. “We tried something new, with new construction techniques. We’re certainly interested in using the same system again.”
What made the project a wow experience for the two home building veterans went well beyond construction speed. For instance:
- Construction Simplicity. Habitat for Humanity relies on donations and volunteers. Mentz admits she was concerned the new system might be a challenge for construction newbies. “We were afraid it wouldn’t be as user friendly as expected. In reality, it was easy.”
- Energy Conservation. It’s too soon for any energy usage metrics for the home. ICF R26 walls typically cut monthly energy expenses by up to half, which won’t surprise Mentz. “Even during construction, the home felt cooler in summer, warmer in colder months. It’s great to see passive heating and cooling in action,” she says.
The home is Energy Star certified. The blower test resulted in super low air infiltration numbers.
- Carbon Impact. Concrete innovations substantially reduce carbon impact.
- Design Flexibility. Hume says the neighborhood’s historic status required several rigorous design reviews. Her brick-clad Queen Anne design was in full compliance. “The neighbors were thrilled by how it turned out,” says Hume. “We were very careful about involving the community, including several walk-throughs with the review committee.”
- Resilience. A cast-in-place, steel-reinforced concrete wall system withstands virtually any weather event, including wind speeds up to 250 mph. The walls are noncombustible and will not weaken, warp, twist or smoke regardless of fire temperature, such as a wildfire.
Mentz and Hume single out the National Ready Mix Concrete Association (NRMCA) and its partners for their generous support. The home is part of the NRMCA’s initiative to construct 50 sustainable concrete homes in 50 states in five years.
Best of all, the new owners are thrilled. “The family is so excited,” smiles Mentz. “The kids ran around their bedrooms imaging what color to paint them!”
Learn more about how ICF building system is delivering superior value, durability, energy performance and sustainability to communities nationwide.