The best fans for a bedroom

A bedroom fan is the most-used fan in the house and the one people choose most carelessly, usually on the wrong number.

Almost every fan is marketed on its maximum: peak CFM, top speed, highest airflow. In a bedroom you will use that setting approximately never.

What you actually do is find the lowest setting that is enough and leave it there for eight hours. So we ranked on:

1. Low-speed wattage, certified where the fan is a ceiling fan. This is the running cost.
2. CFM per watt, certified, for how much air you get for that.
3. Standby power, certified, because it is drawn all year.
4. Speed granularity, because the ability to find “just enough” is worth more than peak output.

We did not rank on noise, and the reason is in the next section.

People buy bedroom fans on quietness, and the data situation is inconsistent in a way worth understanding.

• Ceiling fans publish no noise rating at all. The certification program records CFM per watt, wattage at each speed and standby — and nothing acoustic.
• Portable fans publish uncertified dBA, when they publish anything. The 23 dBA above is Lasko’s own measurement, at a distance and setting they chose. It is useful within a brand and not comparable across brands.
• Many publish nothing. The box fan here has no dBA figure and no CFM figure.
• Bathroom fans are the exception. They are rated in tested sones, which is why that category can be ranked on quiet honestly.

The practical reading: a ceiling fan is generally quieter in a bedroom because the motor is further away and it moves a lot of air slowly. But that is a design argument rather than a measured one, and we are not going to dress it up as data. Sones, decibels and which are certified.

Ninety nights at eight hours each, at 18.34¢/kWh. This is the number that should decide the purchase, and it almost never gets calculated.

The spread from top to bottom is $9.49 over a summer — a 66-fold difference in draw for a job that is, from your point of view, identical.

Note the AC-versus-DC tower comparison in the middle. Two 42-inch Lasko towers: 2.9 W against 37 W at their lowest settings. That is the clearest illustration of what a DC motor buys you — the full comparison.

Worth stating plainly on a bedroom page, because it changes how you place the fan.

A fan does not lower the temperature of a room. It moves air across skin, which speeds the evaporation of sweat and is worth several degrees of perceived temperature — but only to a person in the airstream. A fan running in an empty bedroom does nothing except add its own motor watts as heat.

• Aim it at the bed, not at the room. The effect is on you, so the airflow has to reach you.
• Set the ceiling fan to downdraft in summer. Updraft moves air off the ceiling and does not reach anyone — which way and why.
• It fades in humid air. If sweat cannot evaporate, moving air over it helps less — the mechanism. In a genuinely humid bedroom, a dehumidifier may be the better purchase.
• Turn it off when you leave. There is no reason to cool an empty room with something that only cools people.