Can a ceiling fan box be installed from the bottom?

[reader2580]

My home office is a converted bedroom with a ceiling light. Can I replace the electrical box for the light with a fan box without going up into the attic? The attic is full of blown-in fiberglass and it also has an inch of so of spray foam for air sealing.

 

[Poolshark314]

Yes you can. Pull the old box out and get one of the fan boxes with a spreader bar like this:

Commercial Electric 4 in. Round 1-1/2 in. Deep 15.3 cu. in. Metallic Ceiling Fan/Light Fixture Box and Brace Kit for Old/New Work CMB150-OB - The Home Depot

Provide modish accent to any room in your home by choosing this energy efficient Titan Remodel Construction Brace with Box.

www.homedepot.com

Put the bar into the ceiling and unscrew it until it is tight against 2 joists, then screw the box to the bar you just installed

 

[kbuhagiar]

My home office is a converted bedroom with a ceiling light. Can I replace the electrical box for the light with a fan box without going up into the attic? The attic is full of blown-in fiberglass and it also has an inch of so of spray foam for air sealing.

Yes.

 

[mike93lx]

If you happen to have a joist running through, you can also use one of these saddle boxes


Edit... ******* moment, this isn't a new install.

Commercial Electric 4 in. Round 16 cu. in. Non-Metallic Ceiling Fan/Light Fixture Saddle Mount Box CPB16NM - The Home Depot

Commercial Electric's 16 cu. in. Non-Metallic Ceiling Fan/Fixture Saddle Mount Box allows you to safely install a fan or lighting fixture during new construction or remodel. Featuring a heavy-duty plastic,

www.homedepot.com

 

[SlappyWhite]

First. check what is there and how it is mounted. It may be safe and usable as is.

 

[micromind]

Yes you can. Pull the old box out and get one of the fan boxes with a spreader bar like this:

Commercial Electric 4 in. Round 1-1/2 in. Deep 15.3 cu. in. Metallic Ceiling Fan/Light Fixture Box and Brace Kit for Old/New Work CMB150-OB - The Home Depot

Provide modish accent to any room in your home by choosing this energy efficient Titan Remodel Construction Brace with Box.

www.homedepot.com

Put the bar into the ceiling and unscrew it until it is tight against 2 joists, then screw the box to the bar you just installed

I've installed about a dozen of these over the years, they work well.

 

[wyliesdiesels]

Depends on whats existing and how much access you have

 

[mm08822]

Yes you can. Pull the old box out and get one of the fan boxes with a spreader bar like this:

Commercial Electric 4 in. Round 1-1/2 in. Deep 15.3 cu. in. Metallic Ceiling Fan/Light Fixture Box and Brace Kit for Old/New Work CMB150-OB - The Home Depot

Provide modish accent to any room in your home by choosing this energy efficient Titan Remodel Construction Brace with Box.

www.homedepot.com

Put the bar into the ceiling and unscrew it until it is tight against 2 joists, then screw the box to the bar you just installed

You will have to remove the foam from the sides of the joists where the bracket anchors make contact.

Using the 2-1/8" deep box version could eliminate/minimize interference between the foam and the horizontal bar.

 

[reader2580]

I have no idea how the current box is installed. I don't know if they attached it to a rafter or what. Some people will add wood between the rafters to center the light fixture.

 

[walta]

Let’s not assume the worst and plan on replacing the box, for all you know the current box is rated for a fan.

How old is the house?

Does a stud locator indicate that the joist is next to the box?

Modern boxes will have their weight rating molded into the plastic. Have you looked inside the box?

Walta

 

[nadogail]

I have done this, the sprayed in foam makes it harder, but it can be done.

 

[cgrutt]

As others said what's there now may be good and it depends on how it's attached to ceiling and/or joists now. This video may be helpful note different products available if current box is attached to joist but not rated for fan. Insulation and/or sprayfoam may make it difficult to retrofit without going into attic.

 

[dscheidt]

You can also attach the fan directly to the structure, many fans come with a bracket to make this easy. You still need a box for the electrical connection, but if your existing box is next to a joist, that can be simpler.

 

[reader2580]

I was out of town for a while so I haven’t had a chance to check where the trusses are in relation to the box.

Of course, I want to attach the ceiling fan box to structure. That is the whole point of this project. I think there really isn’t a good way to do this without going up into the attic. The current spray foam is probably going to get in the way of any retrofit product. Also, I would want to replace any damaged spray foam to maintain the air barrier.

Realistically, if I have to go into the attic this project will never get done. I hate sweating that much in the attic wearing a Tyvek suit.

 

[cybrdyke]

If you happen to have a joist running through, you can also use one of these saddle boxes


Edit... ******* moment, this isn't a new install.

Commercial Electric 4 in. Round 16 cu. in. Non-Metallic Ceiling Fan/Light Fixture Saddle Mount Box CPB16NM - The Home Depot

Commercial Electric's 16 cu. in. Non-Metallic Ceiling Fan/Fixture Saddle Mount Box allows you to safely install a fan or lighting fixture during new construction or remodel. Featuring a heavy-duty plastic,

www.homedepot.com

Saddle box is the answer. They can be used in remodel or retrofit. Find a ceiling joist and attach the box to it.
CD

 

[mike93lx]

Saddle box is the answer. They can be used in remodel or retrofit. Find a ceiling joist and attach the box to it.
CD

Kind of hard to justify if there is already a hole, though

 

[cybrdyke]

Kind of hard to justify if there is already a hole, though

True, but it seems to me like he has no other options. He can't/won't use a remodel bar hanger because of spray foam. The existing box isn't fan rated, so he's likely gonna need a new hole, stradling a joist.
CD

 

[sparky 1971]

Since it's a bedroom there's a good chance the box is already fan rated, but to know for sure, the existing light must come down, but because this is GJ, that's way too easy. Every single bedroom I have ever wired, going back to 1994, has a fan rated box (apartments excluded). Some of those boxes have plain old light fixtures mounted to them. And every contractor I have known or worked for had a policy of fan boxes in bedrooms at the rough in. It's not worth trying to save a couple of bucks using a standard box because a builder says the bedrooms get fixtures, then, all of a sudden, out of nowhere, a ceiling fan shows up at trim out.
And when I know for sure there's gonna be a fan, my favorite box to use is a pancake.

 

[reader2580]

I never said I was too lazy to pull the fixture down to check the box. The house was built in 1980 with all kinds of shortcuts so I have my doubts they used a fan rated box, but I'll check.

 

[reader2580]

I pulled down the light fixture, but I don't see anything about the box being fan rated. Part of the box is obscured by fire blocking foam.

 

[Junkdrawer Dog]

Saddle box is the answer. Pulled down the light in our spare bedroom and the joist was right there. The existing box may have been fan rated but I couldn't ascertain from the markings. Anyway...replaced it with a molded box that was clearly fan rated and installed fan. I'd call it a one or two beer job. For reference, this was in a condo so going up in the attic is impossible.

 

[bwringer]

Is there such a thing as, say, a ceiling fan "spider"? I'm envisioning some sort of externally mounted contraption with adjustable arms that extend to screw through the ceiling solidly into the joists above, with some sort o decent-looking cover to camouflage the arms. The box might work sort of as an extender or mud ring that screws into the electrical box above.

You'd lose a few inches, but this could be pretty handy. No idea whether this is legal or even a thing that exists. You could do something similar with some nicely stained wood that matches the trim in the room.


Figure out what the existing box is mounted to; odds are it's hanging on a joist and you can use something like this, or one of the saddle boxes mentioned above.

Westinghouse Fan Master Support Box

The Fan Master Support Box allows you to safely and easily install a ceiling fan or fixture in new construction without having to split wires.

www.westinghouselighting.com

Also, you can get decorative "medallions" to cover all sorts of ceiling sins. This would be a good way to make the room look nice after you create a big enough hole in the ceiling to reach in and do what you need.

 

[walta]

It would be very difficult to find when the box is full of wires while standing on a ladder holding the light fixture in one hand and a screwdriver in the other. All I am saying is consider looking again with a very bright flash light.

Walta

 

[reader2580]

It would be very difficult to find when the box is full of wires while standing on a ladder holding the light fixture in one hand and a screwdriver in the other. All I am saying is consider looking again with a very bright flash light.

The printing is not readable due to spraying the ceilings with paint. The boxes have a light coating of paint in them which makes reading anything pretty much impossible. The box is mounted to a truss.

I thought fan boxes were not yet required by the 2014 NEC, but maybe I overlooked it. (I got a permit and inspection.) I believe my father and I put in the ceiling box when the house was remodeled after I bought it. There was no spray foam in the attic at that point. I never anticipated ever wanting a ceiling fan in this bedroom so I am 99% sure I did not put in one of those ceiling fan boxes that has a support extending from one truss to the other.

 

[sparky 1971]

If it's mounted to the bottom of a truss, it's probably a pancake so get a fan rated pancake box, it would have to perfectly centered for a saddle box to work without having to adjust the sheetrock. If it's nailed to the side of the truss, get one of these:


www.menards.com/main/electrical/electrical-boxes-covers/electrical-boxes/southwire-reg-smartbox-trade-round-24-cu-in-pvc-ceiling-fan-fixture-electrical-box/msbfan/p-7720120058393403-c-6425.htm?exp=false

 

[dscheidt]

Is there such a thing as, say, a ceiling fan "spider"? I'm envisioning some sort of externally mounted contraption with adjustable arms that extend to screw through the ceiling solidly into the joists above, with some sort o decent-looking cover to camouflage the arms. The box might work sort of as an extender or mud ring that screws into the electrical box above.

You're allowed to mechanically attach the fan to directly to structure. I think every fan I've installed has come with a bracket to screw into the joist next to the box. The ones I put up in my house came with a pair of 4" long #12 wood screws for it, even. So you could build a a contraption like yours, but it's easier to screw up a board, and attach the fan to that, or frankly, open up the ceiling enough to install a proper box.

 

[reader2580]

Any ideas on how to cut the nails to remove my round box from the inside? This would be easy with a regular box. I have cut one out before with a reciprocating saw.

 

[sparky 1971]

Pry the box away from the truss with a screwdriver until it's out far enough to cut the nails with a pair of dykes?

 

[GreyOwl]

Any ideas on how to cut the nails to remove my round box from the inside? This would be easy with a regular box. I have cut one out before with a reciprocating saw.

great job for an oscillating tool.