Open-Built Conceptual model
Wall and roof panels.

Wall & Roof Panels

Unity's thick, dense-pack, cellulose-insulated structural wall and roof panels provide high insulation value and the highest standards of airtightness. To ensure the best performance, a "service layer" is added to separate the mechanical systems (mainly wires and pipes) from the thermal shell. This system eliminates drilling and cutting for the "rough in" and also isolates the sealed, airtight shell from penetrations that might compromise it with air or water leaks.

Roof panels consist of engineered lumber framing and dense pack cellulose insulation. The insulated areas have a thickness of 13" (excluding interior ceiling finish or exterior roofing) for an insulation value of R-44. Roof overhangs are detailed with trim finishes to make them appear proportional to the home.

Integrated wiring chase.

Base Chase

The Open-Built base chase is integrated into all of Unity's exterior walls. The chase has enough room to run AC power plus other wired components (networking, stereo speaker wire, and low-power wiring). The chase is finished with millwork chosen to match the finishes in your home. The baseboard is designed to be demountable, simplifying wiring changes.

Open-Built Floor.

Floor System

On Tradd two-story homes, Unity uses the Open-Built second floor system: The floor is supported on a series of metal stand-offs, creating an eight-inch tall space. This space is used to run mechanical systems, ducting, and wiring. The anti-vibration pad on each standoff has the added benefit of reducing noise transmission from people walking on the floor above.


Värm uses an optional system we call Grip-T™ It allows a ceiling to be hung from the I-joists, using our special hangers and wood t-bars. The mechanical systems are then run as normal through the joist layer or below in the hanger layer.

Easy-access ceiling.


Serving as the finish for the floor system, these ceiling panels are crafted from shiplap pine or MDF, and are finished to match your interior design choices. The panels fit together seamlessly, yet are easily removable, granting you access to the mechanical systems above. An easily dismountable and remountable ceiling also makes repainting a snap.


House Systems Reorganized

Open Building (OB) is an innovative approach to design and construction that enhances efficiency, while increasing the variety, flexibility and quality of homes. In the OB perspective, a building is a well-organized combination of disentangled systems, leading to increased standardization, simpler, more flexible design, and higher quality.

Developed by Bensonwood, Open-Built® is a suite of innovations and practices created to apply Open Building principles to home design and construction. In the Open-Built home, the various mechanical systems are strategically disentangled from the structure and space plan of the home, creating more logical "layers," creating many benefits. Open-Built organization provides a much easier method for installation during construction, while also allowing access for future alterations, upgrades, and new technologies. In this way, the Open-built home can more easily adapt to the changing needs of its occupants over time without the waste, expense, and disruption normally encountered.

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For research, information, and highest regarded opinion about high performance buildings, we refer to Green Building Advisor