Back in 1966, Canadian contractor Werner Gregori was awarded a patent for a foam concrete form block, measuring 16 inches high by 48 inches long with: a tongue-and-groove interlock, a waffle-grid core and metal ties. This new block technology became the basis of insulated concrete form (ICF) construction, a method where hollow foam blocks are stacked to shape the exterior walls of a building, reinforced with steel rebar, and then filled with concrete.
"ICF has been around a while, but really started to become more mainstream over the last eight years," says Rod Fetters of ICF Specialist, based in Litchfield Park, Ariz., which designs buildings using the foam block technology. "We did our first worship space back in 2004, and it's become a great option for those who want to find new ways to build."
By combining one of the finest insulating materialsExpanded Polystyrene (EPS), with steel reinforced concrete, ICF results in a wall system second to none.
COST VS. BENEFITS
The cost is only a few percentage points over building with wood, but the 40 to 70 percent savings on energy costs will offset the upfront difference rather quickly and the savings will continue over the life of the structure.
The benefits of building with ICFs are many. They allow buildings to be built stronger, more energy efficient and more environmentally friendly. ICF walls are virtually airtight and take advantage of the dozens of yards of concrete in the walls to moderate temperature swings.
The method is also fire rated up to four hours, is termite resistant, improves air quality, is mold and mildew resistant and is Energy Star Certified.
ENERGY EFFICIENCY EXTREME
"The performance of an ICF wall exceeds typical walls because of more insulation, less air infiltration, and higher mass," Fetters says. "The concrete provides exceptional strength and thermal mass; the foam provides a continuous layer of one of the world's best insulators, and is an ideal substrate for many finishes."
That's why many churches have started to utilize ICF techniques in their worship facilities, and both new and existing churches are reaping the benefits.
"Energy efficiency is the biggest thing that churches appreciate," Fetters says. "Some of these master churches, these supersize, big tall structures that we do, can burn though a $20,000 a month utility bill, and ICF can knock that down by about half."
Recently, ICF Specialist worked on St. Juan Diego Catholic Church in Chandler, Ariz., and the facility is seeing energy savings thanks to the high thermal mass walls that provide even temperatures. The church said that its energy bills have dropped considerably.
Another big pro of using ICF methods is its noise reduction capabilities, thanks to a strong combination of concrete and foam.
Sound attenuation was one of the reasons that Sun Valley Community Church in Gilbert, Ariz., decided to employ the technology in its 84,000-square-foot facility. Since the church was using its worship hall, classrooms and mezzanine all at the same time, it wanted a sound barrier that could allow for this to happen. ICF blocks did the soundproofing job nicely.
"Acoustics are a big concern for most churches, and these have an STC rating of 51, which makes for a very quiet space. Worship clients especially enjoy that," Fetters says. "That's why you are seeing a lot of movie theaters and hotels switching to ICF, as well. The sound quality is great."
Churches that are located in areas prone to hurricanes or floods will be happy to learn that ICFs are resilient and can withstand severe weather events better than stick-built construction.
A huge benefit, Fetters says, is that building with ICF is quicker, so a church can get things up and running a lot sooner.
Constructing a normal supersize church takes somewhere about 8-10 weeks, which is weeks earlier than building with non-ICF methods.
Additionally, ICF construction is a lot quicker and safer. In almost all cases, worker's comp is decreased because the blocks are light and a benefits masonry and concrete guys, who are not getting as worn out as they do with more traditional building methods.
Fetters says it's as easy as putting Legos together, and stacking them up just like they would a normal stud. Once they are all in place, they can be filled with concrete and the building takes shape. And because the foam panels remain in place after the pour, the building season can be extended in colder climates because