Part of the test home’s mission is to determine what systems can save the most energy costs for the greatest return on investment while still providing a comfortable environment for the occupants. As such, the project team is testing three separate HVAC distribution systems:
A standard system with full-capacity, large ducts using traditional materials. This system will serve as the control during testing.
Smaller ductwork (about half the size) made with PVC pipe. Though not yet code approved for this use, this material is readily available and is inherently tight, so there is less chance of leakage due to improper installation.
Heated and cooled air provided to only two points in the house, one in the main living area and one on the second floor, each zoned with a thermostat. The team hopes that over-the-door transfer grilles will provide convective movement of air from the conditioned hallway to non-conditioned bedrooms.
During testing, researchers will be able to switch between the three systems. In addition, the team will compare data from the home’s traditional heat pump versus its ground-source heat pump.
Among other systems being tested are varying lighting schemes that combine CFL, incandescent, and LEDs, and a look at how the Energy Star-rated appliances perform as part of the whole house. The team also will study the impact from a “desuperheater,” which transfers waste heat from the heat pump to water, and will experiment with a heat recovery system from drainwater.
Though the house uses readily available products and building methods, replicating the techniques will still require retraining and rethinking, which IBACOS recognizes and anticipates. With education a key component to the Lab Home, the team dedicated countless hours to drawing up detailed plans explaining how to build the envelope, including isometric drawings, sections, and step-by-step protocols. Due to the extreme air tightness of the building, window installation, for example, requires 17 steps versus the builder’s typical five, all of which is explained in detailed drawings.
In addition to those resources, an online schematic, launching soon, will allows visitors to peel back the house layer by layer to view the techniques and details.
But more than just training during and after the fact, subcontractors—management and the installers in the field—played an integral role in planning. “We wanted to engage the subs as much as possible throughout the process,” says Brozyna. “We brought the contractors into the office in groups. We all sat down together and said, ‘This is the objective of the project. What do you see as the challenges? Have you seen these types of details before? Are we thinking about this the right way? Have you seen this done better ways?’”
“We learned as much from the trades as they learned from us,” Brozyna recalls. “Engaging them throughout the process got buy-in from them. … Asking their opinion and getting their feedback made them feel part of the process.”
THE NEXT THREE YEARS
Unlike a traditional home, no moving truck pulled up to the Lab Home after ribbon cutting. Instead, electronically controlled testing—tracked by more than 300 sensors—will simulate the lifestyle of a typical family of four for the next three years. The goal is to see which methods are most effective—and which aren’t practical or don’t deliver enough ROI.
“Energy efficiency has always been one of the biggest parts of what we’ve done,” says Chris Schoonmaker, vice president of S&A Homes. “With the Lab Home, we’re going to be able to learn as we go through the process, and over time, put these things into practice in a cost-effective manner.”
The project also serves to educate local homeowners and the community about what a high-performance home really looks like, he notes. “People realize that there is a movement out there to get homes more efficient and that we really believe in it.”
Katy Tomasulo is deputy editor for EcoHome.