Why warm air stays at the ceiling, and what to do about it

You may have noticed that a room can feel cool at floor level even when the radiator is hot. Nothing unusual about that: it's simply how heat moves.

Convection in a nutshell

A water radiator warms the air that touches it. That air becomes lighter, rises along the wall and collects under the ceiling. Cooler air sinks, passes the radiator, and the cycle starts again. This movement is slow, and heat takes a while to spread.

What this means day to day

• The room takes a long time to become comfortable.
• It can be noticeably warmer up high than down low.
• People tend to turn up the thermostat to compensate.

How to spread the heat better

• Free up the radiator: avoid furniture, thick curtains or laundry in front of it.
• Maintain it: a clean, properly bled radiator heats better.
• Help the air circulate: that's what a fan placed under the radiator does, pushing warm air into the room.

To find out more, see how our fans work.