Radiators under windows.

BTW, a friends home built large but super insulated house has a modest heating demand, but would be uncomfortable with no heating. It is heated by a single loop of wide bore pipe through which water heated by a solid fuel stove circulates by gravity. No radiators are used, the pipe IS the radiating surface.

The heating pipe runs around the entire perimeter of the upper floor before descending to the stove.

This arrangement slightly restricts furniture layout, but has worked excellently.

With a good fire as would be used in winter, the heat output to the water is estimated at about 6Kw, with another 6Kw into the room containing the stove. About half that with a modest fire.

In moderately cool weather the fire is lit each evening and allowed to go out during the night. In colder weather the fire is lit 24/7.

BTW, a friends home built large but super insulated house has a modest heating demand, but would be uncomfortable with no heating. It is heated by a single loop of wide bore pipe through which water heated by a solid fuel stove circulates by gravity. No radiators are used, the pipe IS the radiating surface.

The heating pipe runs around the entire perimeter of the upper floor before descending to the stove.

This arrangement slightly restricts furniture layout, but has worked excellently.

With a good fire as would be used in winter, the heat output to the water is estimated at about 6Kw, with another 6Kw into the room containing the stove. About half that with a modest fire.

In moderately cool weather the fire is lit each evening and allowed to go out during the night. In colder weather the fire is lit 24/7.