How Much is a Fart Fan?  

Humorous as it may sound, as the summer months approach and drag on, more and more people each year perform a Google search of variations of the phrase, “how expensive is a fart fan?” While it might seem strange, it’s not as silly a question as it might sound. The key to finding out how much you will need to spend to equip your bathroom with an adequate bathroom fan is based on the fan’s cubic feet per minute (CFM) and how quiet it is.

The fact is that the cost of “fart fans” or bathroom fans depends on the space it is to be installed in and the “load” it is expected to carry. The larger your bathroom is, the more air that your bathroom fan will need to be able to circulate. The CFM rating of a bathroom ventilation fan reflects the square footage of the bathroom in question.

The noise that a bathroom vent fan produces is measured in units called “sones.” One sone is roughly equal to the noise produced by a quiet refrigerator. The lower the sone number on the fan, the quieter it should be.

The greater the CFM of a given fan, the larger and more powerful it will tend to be. Clearly, larger and more powerful fans will be more expensive. Reducing the sones on a fan requires some special engineering on the part of the manufacturer. The finer the engineering on the fan motor and the more insulation or soundproofing is built into it to reduce the sone rating, the more your fan will tend to cost. It might be worth noting at this point that the larger and more powerful a fan is, the more expensive it will be to soundproof it thoroughly.

Calculating the Cost of a Bathroom Exhaust Fan

Fortunately, you do not need to hire a contractor to figure out what kind of fart fan you need to buy. Simply follow this formula, and you’ll be able to identify the level of bathroom fan you need.

1. Measure Your Bathroom

Using a tape measure, measure the length from each opposing wall as well as the distance from the ceiling to the floor.

2. Calculate Floor Space

Multiply the width by the length of the room. For example, if your numbers are 5.5 by 7.8, you should have 42.9 square feet of space. If your bathroom has a complex ceiling and/or floor plan, you might need to break the calculation into several parts and add the results together.

3. Calculate Volume

Multiply the floor area by the height of the ceiling. If your ceiling is 8 feet high (and level) you would multiply 42.9 by 8, which equals 343.2 cubic feet.

4. Calculate CFM

Once you’ve gotten this far, the rest is easy. CFM is equal to cubic feet divided by 7.5. For our example, 343.2 / 7.5 = 45.76. That’s the ideal CFM you’re looking for. Simply buy a fan with a rating equal to that number.

Bathroom Fan Cost Per CFM

To answer the question simply, the national average price for your ideal bathroom fan is $350 to $400. In the lower range, you can find a good bathroom fan for $70 to $100. At the higher end of the spectrum, expect to pay $500 to $800.