Heat pumps + a Sophab: better together

Heat pumps are the workhorse of low-carbon heating, but they work harder in the cold. A Solar Passive Habitat gives them a hand.

Warmer air in, less work done

At the smallest scale, a Sophab can be a simple cover over an outdoor heat-pump unit, tempering the air around it on sunny winter days so it runs more efficiently. At full-house scale, the arch pre-warms the space the heat pump has to condition — so the same equipment delivers more comfort for less power.

Sophabs come in every size between those two, from a heat-pump cover to a full Solarship — a whole home in a dome.

Build the small one yourself, free

The cover is the one Sophab you can build in a weekend, so we give the plan away: twelve pages with three sizes, a one-sheet cut list, ground and wall-mount assembly, and the airflow clearances that keep your unit safe. No charge, and nothing to install to read it.

Get the free heat-pump plan → Or size one for your whole home →