concepts · updated 2026-07-19
Timothy Maloney
confidence: medium volatility: cold verified: 2026-07-19fresh
Inventor and founder of One Design Inc. Developed rotationally-molded water-wall modules for passive heating and cooling starting in 1974, evolving over four generations. Baer names him explicitly in the Cool Cell brochure's "Past Work" section, alongside Harold Hay and Shawn Buckley, as a direct predecessor.
Inventor and founder of One Design Inc. Developed rotationally-molded water-wall modules for passive heating and cooling in the late 1970s–early 1980s. Baer names him explicitly in the Cool Cell brochure’s “Past Work” section (2002), alongside Harold Hay and Shawn Buckley, as a direct predecessor:
“Shawn Buckley introduced passive wall-modules to capture heat and coolth; Harold Hay used roof-ponds; Tim Maloney used rotational-molded water-walls.”
Development history
Per David Bainbridge’s water-wall history, Maloney — influenced by both Baer and MIT’s Hoyt Hottel — began testing water-wall module systems in 1974. The first generation used plastic bags supported between sheet-metal panels; problems with that and subsequent designs led to a fourth-generation design of stackable plastic water tanks (roughly 2’×8’×1.5’) sized to fit a stud-wall cavity. One Design’s houses using these systems were described as effective and attractive.
Patent portfolio (One Design Inc)
| Patent | Title | Key tech |
|---|---|---|
| US 4,257,477 (1981) | Environmentally driven heating and cooling system | Water containers behind south-facing glazing; spray-cooled for summer; field-erectable modules |
| US 4,263,765 (1981) | High mass wall module | Concrete-fill or massive-fill modular wall blocks stacked to make walls |
| US 4,290,416 (1981) | Phase change energy storage panel | Glauber’s salt containers behind south glazing; pivotally mounted for reversibility |
| US 4,355,682 (1982) | Environmentally driven heating and cooling system | Continuation/refinement of US 4,257,477 |
The phrase “rotational-molded” is significant: Harrison’s integral roof cooling container (US 5,609,200, 1997) used the same manufacturing method on roof sections. Maloney was doing it on walls ~15 years earlier.
Unknown
Location, biography, and whether Maloney and Baer had direct contact are not in the archive. One Design Inc’s fate is unknown.