FAQ: Are Bathroom Exhaust Fans Standard Size?

Bathroom fans are not standard size. The housing dimensions vary across different models. The duct size is standardized. On most bathroom fans there is a 4 or 6-inch duct.

How do you measure a bathroom exhaust fan?

Measure the length times the width times the height of your bathroom. Divide that number by 60, which is the number of minutes in an hour. Then multiply that number by eight, which is the suggested number of air exchanges that you should have in your bathroom each and every hour.

Are all bathroom extractor fans the same size?

Are bathroom extractor fans a standard size? Domestic extractor fans tend to come in two sizes: 4 inch/100mm and 6 inch/150mm. This size refers to the size of the impeller (the revolving part inside the extractor fan that sucks the air out).

What is the diameter of a bathroom exhaust fan?

4” or 6” Duct for Bathroom Fan The two most common duct diameters for bathroom fans are 4” and 6”, and there is a good reason for this. First, you need to know that the size of the bathroom determines the fan capacity you need (you can calculate the correct CFM rating your bathroom fan needs here).

Do exhaust fans come in different sizes?

In general, choose a fan that can move at least 1 CFM per square foot of room. So, for an 80 square foot bathroom, select an 80 CFM fan. For bathrooms 50 square feet and smaller, it’s recommended you purchase a bath fan designed for small rooms. In other words, choose under 79 CFM bath fans.

How do I know what size exhaust fan I need?

Calculation:

1. Area of the Room=Length x Width x Height.
2. Area of the Room=10 x 15 x 10 =1500 Cub. Foot.
3. From the table Air Changing Rate (ACH) for Bathroom = 8 Times/Hour.
4. Size of Ventilation Fan = (Area of Room x ACH ) / 60.
5. Size of Ventilation Fan = (1500 x 8 ) / 60 = 200 CFM.
6. Size of Ventilation Fan = 200 CFM.

How do I know what size extractor fan I need?

To work out the extraction rate, you need to calculate the cubic metres of the room you want the fan to go in. Do this using a measuring tape by noting down the height, width and length of the room in metres. Once you have this information, multiply the three figures together to get the size in cubic metres.

Does a bathroom exhaust fan need to be vented outside?

Bathroom fan installation requires outside ventilation. If the fan isn’t accessible through an attic, you’ll need to vent through a sidewall of your house. Letting the fan exhaust into an open attic will cause moisture buildup on the underside of the roof. Avoid venting through a soffit vent or ridge vent.

How do I choose a bathroom extractor fan?

The most important things to consider when purchasing an bathroom extractor fan:

1. Learn about bathroom zones.
2. Consider when you want your fan to operate.
3. Think about noise levels.
4. Research different designs.
5. Decide on your air exchange rate.
6. Think about exterior grilles.
7. Consider a heat recovery option.

Can I replace bathroom extractor fan myself?

If you only need to replace an extractor fan, swapping old for new, you should be able to use the existing wiring, ducting and exhaust venting. It’s a straightforward DIY job that only requires basic disassembly and securing screws. Also check the dimensions of your new fan line up with the existing holes.

How do you buy an exhaust fan for a bathroom?

To get the right fan for your bathroom, use the guidelines set by the Home Ventilating Institute: Your fan should have 1 cfm for every square foot of floor space in your bathroom. For bathrooms larger than 100 square feet, figure your cfm requirements by adding: 50 cfm for every toilet.

Does a half bath need an exhaust fan?

A half-bath (normally that means no tub or shower) will not have as great a need for ventilation as a full bath, but it still needs a fan or window. If you install an exhaust fan, you must vent it to the outside.

Is it bad to oversize a bathroom exhaust fan?

Bathroom vent fans are rated for the amount of air they can move, measured in cubic feet per minute, or CFM. First, it’s a good idea to oversize the fan slightly. In our sample 54-square-foot, for example, it’s a good idea to install a 60 CFM fan for good measure.

What does 1.0 sones sound like?

1.0 sone: A 1.0 sone rating is roughly equivalent to the sound of a refrigerator running. 2.0 sones: 2.0 sones is the noise level in a normal office workplace. 3.0 sones: A fan rated at 3.0 sones will be roughly as loud as a face-to-face conversation.

What does 1.5 sones sound like?

Sound levels are measured in sones. Spot fans are typically rated at 3 to 4 sones, though some can be quite a bit louder. Fans rated at 1.5 sones are very quiet, and low-capacity fans rated as low as 0.5 to 1 sones are nearly inaudible.