Introduction

Introduction

Air is often treated as an invisible, neutral background to architecture, yet it is a critical medium, that shapes human comfort, environmental performance, and spatial experience. In architectural design, air is actively organized and controlled through complex building envelopes and ventilation systems. These decisions are particularly important within residential buildings because people spend so much time in them thermal comfort and ventilation is particularly important. The design of walls, openings, materials and environmental systems all contribute to how air is integrated, distributed and contained within a building, making it a fundamental yet often overlooked practice.

This essay examines two experimental residential projects in Illinois, the Dome Cluster House by Michael Jantzen, 1982, and the Illinois Lo-Cal House, 1976, developed by the Small Homes Council-Building Research Council. These projects have very distinct form and design approaches, but both were developed within very similar geographical and climate context of central Illinois and within a relatively close time frame shaped by the energy concerns of the 1970s. This shared context allows for a focused comparison of how architects working under similar environmental conditions and historical conditions developed very different strategies for managing air within residential homes.

The seasonal extremes of Illinois pose specific challenges for residential design. Illinois is known for its hot and humid summers accompanied by cold winters. Buildings must simultaneously address heat gain, heat loss, humidity, and ventilation across dramatically shifting seasonal conditions. Both projects respond directly to these environmental constraints but have different views on air as a medium. The Dome Cluster House approaches air as a dynamic and interactive element. Jantzen focuses on adaptability and environmental responsiveness. The Lo-Cal House, in contrast, treats air as a controllable component within a highly efficient tightly regulated and calculated system. Reflecting the Small Homes Council-Building Research Council’s emphasis on precision, insulation and containment.

By analyzing these two projects together, this study focuses on how these buildings control and mediate air, and what design logics define the environmental strategies. Through this comparison we can examine how differing architectural approaches, experimental versus research-driven, produce distinct models of thermal comfort and atmospheric control within the same regional and historical context.