What heats faster, dry or humid?

[QiQuesti]

Does a humid room heat up faster than a dry room? Will a humidifier help heat a room faster than a dry, non-humid room?

[wildwood]

No, dry air heats up much easier.

Running a dehumidifier at a sensible level will help to make your home healthier and easier to warm up.

[heathfield]

Think how long it takes to bring water in a kettle to 100 degrees C, when it boils.

Now imagine how long it would take to bring the air in an empty kettle to that temperature. A fraction of the time!

Roughly speaking, the same sort of thing is happening when you have high humidity in your room - a lot of extra energy is needed to heat that water vapour.

[mibn2cweus]

About the same. Moisture displaces other on average heavier elements in the air. As a result humid air is less dense than dry air.

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