Weight of bathroom fan a concern on 2x2's?

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Posts: 17
Joined: Sat Jun 27, 2009 6:38 pm
Location: NEPA

Fri Jul 24, 2009 3:59 pm

Hi everyone!

This is my first post but I have been lurking for a bit.

I am remodeling the bathroom in my 1984 Commodore double wide and I am adding a bath fan (didn't have one before).

My concern is the weight of the fan in the ceiling if I mount it to the 2x2's that are used to hang the existing ceiling sheet rock. I bought a Nutone 765HFL with the fan light and heater. The unit weighs just a hair shy of 16 pounds (15 lb 15 oz).

The 2x2's are the base of the roof trusses (peaked roof) in the back bathroom, the first located 32 inches from the back wall and the second about 16" on center at 48 inches from the back wall. The fan would then be located approximately 3 feet from the marriage line of the two home halves. The 2x2's feel solid enough when pushing on them, but I just wanted to ask if I should be concerned about the weight; maybe add some additional reinforcement around the fan unit or should I leave it alone and just mount the fan as is? BTW, it is IC rated for insulated ceilings.

Has anyone run into this situation and is it a cause for concern? Sorry to be so long-winded on my first post.

Chris :?:

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Sat Jul 25, 2009 2:36 am

I think that may be too much weight to hang just off of the bottom cords of truss. Hopefully you plan on venting the fan duct out the roof over the fan. Then, maybe you would be able to add some extra support to the bottom cord from the top cord. No engineering or guarantee on this. But if you had a solid connection from the top to the bottom cord and maybe some way to attach the fan where it would get support from two reinforced trusses, it might be strong enough to hold the weight.

You may be venturing off into uncharted territory here, so you would have to be creative. There probably is a risk that the ceiling would bow due to the weight of the fan. But if it were me, I would think I could reinforce the trusses to work.

What might be a better idea is using a mobile home, lighted, ceiling exhaust fan. I doubt it is as good of a product as what you have, but it is made for mobile home ceilings and very lightweight. You can find these at mobile home parts outlets, such as www.randgsupply.com.


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All information and advice given is for entertainment and informational purposes only. The person doing the work is solely responsible to insure that their work complies with their local building code and OSHA safety regulations.

Posts: 17
Joined: Sat Jun 27, 2009 6:38 pm
Location: NEPA

Sat Jul 25, 2009 11:00 am

Thanks for the input JD; I needed another viewpoint on this.

I was actually more concerned about additional weight on the roof trusses and roof structure and hadn't even thought about the ceiling bowing!

I had some other ideas (wild stuff, not practical). What I think I will do is run a 2x4 across the the room on either side of the fan unit and secure the 2x4's to the top plates of both walls. Then I can secure the bottom cords of the roof trusses to the 2x4's in the area of the fan box. The room is only 55 inches wide, so running the 2x4's like I-beams across the wall tops won't add any additional load to the trusses but will reinforce the truss structure around the fan.

Thanks for helping me think a little bit more about this.


Brenda OH reregister
Posts: 45
Joined: Fri Aug 08, 2008 6:47 pm

Mon Jul 27, 2009 9:43 am

Hi Chris,

I used the smallest home fan from home improvement store. without a light, that has the hose/duct run out the side of the fan, and attached it on the surface of the ceiling. The bathroom is very small, I am getting plenty of air flow for removing odors, haven't had hot water to see what it will do for steam, but it should be fine, the room is tiny.

I had a junction box there flush mounted in the ceiling, the vent attached to it on the surface. I may also have used a dry wall anchor on one end.

The surface mount is not going to be a hazard for hitting heads on it in this case, the vent is located above where the washing machine will be.

I then ran the ducting out the side of the home, instead of adding a hole to the roof. I did this because the ducting went into the water heater closet space and did not show, and I knew I could seal a hole in the wall easier and better and with less chances of leaks than I could do the ceiling. Also, using a home vent model will make a replacement easier in the future.

I had to enlarge the duct from the fan size to a dryer size to use a dryer vent cover outside, but that was again a standard part they carried at the store, no special order.

The no light, smallest air exchange vent was only $14, and not heavy at all.

for lighting, I added a small track light, only using 1 of the lights instead of the 3 that came in the set, very light weight again.

hope that gives you some more ideas and options.

Brenda (OH)

Posts: 17
Joined: Sat Jun 27, 2009 6:38 pm
Location: NEPA

Fri Jul 31, 2009 7:59 am


I originally thought that I would use a basic vent fan w/o light like you have done. My wife saw the electric radiant floor mats in the store and thought that would make the bathroom floor warmer in the morning. Unfortunately she does not want a tiled floor in the bathroom (slippery). Since the electric radiant mats are not recommended under sheet vinyl, she was disappointed.

I also vented out through the wall as I had no inclination to put more holes in the roof. Our other bathroom has a vent through the roof and when it rains there is some degree of water that makes it into the room. That unit needs to be looked at and replaced anyway. It is 15 years old and I don't think that it does anything but make noise :roll: ; no air movement that I can tell.

While we have a propane forced air furnace, our main source of heat in the winter is a pellet stove (nice and toasty), so there is usually no air moving through the vents. When I saw this fan/light/heat combo unit I figured that the heat should make her more comfortable in the bathroom on those cold mornings. Needless to say if the woman of the house is happy, all is well! :D