Mechanical Systems for a Low-Load, High-Performance Home – GreenBuildingAdvisor

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Part 4 of a series on a Kansas home built from reclaimed materials examines how a high-performance enclosure reshaped the project’s mechanical design

This is part 4 of a series on a Kansas house built from reclaimed components. You can read the first part, an introduction to the project, here; the second part, on the engineering challenges of using reclaimed materials, here; and the third part, on building a high-performance enclosure with reclaimed insulation, here.

By the time the Haberman residence reached the mechanical-design phase, many of its biggest decisions had already been made. Previous articles in this series explored how salvaged materials shaped the structure and enclosure—from reclaimed steel and heavy timber to site-built wall and roof assemblies incorporating salvaged insulation.

Those decisions also shaped the mechanical design. With an exceptionally airtight enclosure, continuous exterior insulation, and very low heating and cooling loads, the question was no longer simply how to heat and cool the building, but rather how to deliver comfort while managing humidity, ventilation, and indoor air quality without compromising the performance of the enclosure.

From the outset, the homeowners envisioned a house where comfort would come quietly, without the drafts or visual clutter associated with conventional forced-air systems.

But as construction progressed, equipment availability, system complexity, and the realities of executing a one-of-a-kind project forced the team to rethink that approach.

The result is a mechanical design that is less unconventional than originally envisioned, but one that reflects the same philosophy seen throughout the project: adapting to the realities of construction while preserving the original performance goals.

The Original Vision: Comfort Without Air Movement

Long before mechanical equipment was selected, the homeowners had a clear idea of how they wanted the house to feel.

“We still wanted the same comfort, and we took the principle that we didn’t want floor vents or air blowing up on us,” homeowner Brandon Haberman says. “We wanted the cool air to blow up…