Do I Need A Permit To Install A Bathroom Fan?
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Home improvement projects range from simple to complex, but even some tasks you might consider easy require a permit. Even the most experienced DIY lovers can’t ignore when they need a permit for specific jobs, so make sure you’re informed.
You need a permit to install a brand new bathroom fan, but not if you are simply repairing or replacing a fan or motor. Installing a new fan unit and ventilation can be a slightly challenging DIY job, plus it involves working with electricity. Therefore, you’ll likely need to call in an electrician, among other professionals, to do some of the work and pull the correct permits.
Many expert DIYers might forgo the permit and just do the job themselves. Others might choose to save some money and hire someone on the side to install their bathroom fan. However, it’s important to understand the risks; permits ensure that a job is done correctly and safely.
What Permits Do I Need To Install A Bathroom Fan?
Depending on what your specific job entails, you might require multiple permits. Installing a brand new fan unit involves electrical, venting and ductwork, and cutting a hole in your wall or ceiling and roof. Therefore, you’d need a permit for ductwork, another for wiring, and a third for roof modifications.
Permit requirements, processes, and prices vary by jurisdiction, so it’s important to contact your local permit office for specifics. However, here are a few guidelines regarding the different permits you might need for installing a bathroom fan.
1. Electrical Permit
Typically, the electrician pulls the permit for the work they will be doing. However, if the homeowner will be doing the work, in some cases, they can purchase the permit.
If you plan to hire a professional, they purchase their own permit; you can’t purchase it for them. You must also ensure you purchase the permit from the correct jurisdiction based on the jobsite.
Don’t let any work commence on your project until you or the professional has purchased the permit. Inspectors will typically follow the National Electric Code (NEC). Depending on the work being done, a permit for wiring can cost anywhere from $30 to $500.
2. Ductwork Permit
When you’re running ductwork to properly vent air from your bathroom to the outside, you need a permit. Once again, whoever is doing the work will need to purchase the permit, which can cost between $30 to $500.
Typically inspectors or certified testers will need to make sure the ducts are installed and sealed properly. In some areas, you may need to provide a design of the planned ductwork before proceeding.
3. Roofing Permit
If you are making modifications to your roof, you generally need a permit. Since to install a new vent fan, you’ll be cutting into your roof, this qualifies.
A permit for roofing modifications can run anywhere from $70 to $250. It depends on the location and scope of work. Always check with your local code and inspection office to get specific details about your area.
Do I Need A Permit To Replace A Bathroom Fan?
But what if you already have a bathroom fan? Maybe you’re just replacing the fan motor, but everything else (like wiring and ventilation) stays the same. Do you have existing ductwork venting outside through the roof and don’t plan to change it?
If so, you won’t need to worry about the ductwork permit or roofing permit. You likely don’t need to worry about the electrical either if you’re not running new wiring and simply swapping out a similar fan. Typically, you’ll just need a permit when you install a bathroom fan for the first time.
How To Replace A Bathroom Fan
If you simply want to switch out your existing fan, follow these steps.
- Switch off the power to the fan at the fuse box and use a circuit tester to ensure there’s no live current.
- Remove the old fan, leaving the existing wiring and ductwork intact.
- Assemble the new fan according to the manufacturer’s instructions.
- If you purchased the same size fan, it should fit nicely. But if it is a little too large, cut the hole in the ceiling a little larger. Make sure you don’t cut any wires or the ductwork; you’ll break the seal.
- Use duct tape or clamps to secure the duct connector on the fan to the duct.
- Connect the existing wire by pulling it through the hole and into the housing. The manufacturer’s instructions will include a wiring diagram for you to reference. Make sure to connect the wires and power cable according to these instructions.
- Ensure the rim of the fan housing lines up with the hole in the ceiling, and slide the grille into place.
- Flip the power back on and test the fan.
If you have decent DIY skills, this can be a reasonable job to tackle on your own. However, if you’re not comfortable with the task, it’s best to call a pro to replace the fan.
If you end up making too big a mistake, it could turn a small job into a big one–then you might need permits. For example, you cut the wiring and need an electrician to rewire something.
Or something happens to the duct that is irreparable. Then, if you need to run new ductwork, you’ll technically need a permit, etc.
Why Do I Need A Bathroom Fan?
Bathrooms are notoriously damp and humid places, thanks to hot showers and baths. Without proper ventilation, this humidity creates condensation on the bathroom’s surfaces. This can lead to peeling paint, rotting wood, foul odors, mold, and other issues.
In most states, building codes require that a bathroom has ventilation. Therefore, you need to have either a functioning window in your bathroom or an exhaust fan.
The fan pulls the humid air and odors out of the bathroom, directing it outside to keep your bathroom dry. It’s a good idea to run your bathroom’s exhaust fan for about 15 to 30 minutes after showering or taking a bath.
Additionally, if your toilet is in a separate, closed-off space, you will most likely need a separate fan in this area.
Frequently Asked Questions
Where should I install a bathroom exhaust fan?
Usually, you’ll find bathroom fans on the ceiling since hot air rises. If your fan has any type of heater or light, you should also install it on the ceiling.
However, some bathroom fans can go in the wall. But it should specify in the instructions that you can wall-mount the fan. If it doesn’t, check with the manufacturer before installing the fan.
If you do install the bathroom fan in the wall, mount it as close to the ceiling as you can. This way, you can make sure it works as efficiently as possible, pulling all of the hot air from the room.
About how long does it take to install a bathroom exhaust fan?
If you already have a bathroom fan and are just replacing it, it will take a couple of hours. If you’re installing a brand new unit, plan for as long as 8 hours. Of course, a lot depends on your expertise and how much ductwork you need to run.
If you plan to hire a pro, the cost to install a new fan can be anywhere from $400 to $950. This includes the parts and labor. If you’re replacing an existing fan, it will likely cost about $150 to $300, or as much as $500 to $550. The latter will be if any adjustments need to be made to the existing setup.
How do I know what size bathroom fan to get?
You purchase a fan based on its CFM rating, which expresses how much air the fan can move. It’s essential to get a fan the right size, as one that’s too small won’t work efficiently in your space. It will also likely burn up and wear out faster than a correctly-sized unit.
In an average-sized bathroom, you can get a fan with a CFM rating that matches your bathroom’s square feet. For example, if your bathroom is 60 square feet, you need at least a 60 CFM fan.
However, if you have a long run of ductwork or it makes a lot of turns, you’ll need to increase the CFMs. This is because the air will have farther to travel to make its way outside. Additionally, if you have ceilings taller than 8-feet, you might want to consider upping your fan’s CFM rating.