Hanging Light Fixture From Drywall - Low Tech Test

[mrbill24]

I've been trying to decide how I want to mount an ATI 48" 6 bulb T5 fixture, and my preferred setup would be to hang it from the ceiling. My dilemma is that the studs in my ceiling do not allow the fixture to be centered over the tank. Some options that have been used by other people on this board have been:

1) Secure the cables to the studs and adjust the individual cable lengths to center the light over the tank (resulting in the wires not being parallel).

2) Go into the attic and install a cross brace between the studs

3) Bend some electrical conduit into a hanger

Some people have also used the little spring loaded toggle bolts and supported the fixture purely from the drywall. Hanging a 25-30lb fixture from drywall alone would cause me to lose sleep at night, but I do not have any access to install a cross brace. So, I decided to do a little low tech drywall test.


According to a little online research and the guy at Lowes, 5/8" drywall is used on the ceiling in newer homes. To build in a little extra saftey margin, I decided to test 1/2".

The pictures pretty much speak for themselves. You are looking at a 24"x24"x1/2" section of drywall suspended between two chairs (unsupported length 23"). The barbell weighs 35lbs. I would say the deflection is right at 1/16". The anchor is a 3/16" "toggler" brand drywall anchor. I plan to also test a 1/8" traditional style spring toggle anchor. My worry was more the drywall giving way due to the bending forces rather than the anchor pulling through.

http://i406.photobucket.com/albums/pp150/mrbill24/IMG_9559.jpg

http://i406.photobucket.com/albums/pp150/mrbill24/IMG_9558.jpg

http://i406.photobucket.com/albums/pp150/mrbill24/IMG_9561.jpg

http://i406.photobucket.com/albums/pp150/mrbill24/IMG_9560.jpg

[flyyyguy]

cool test. thanks for sharing

thats pretty good support it seems. I still wouldnt sleep well with it for soem reason though, even though it looks pretty dang trustworthy. lol


I have a 5th way you could put on your list. Has to be done before building but I actually installed 1/2" osb behind the drywall in my fishroom so I can hang the lights or anything wherever I feel. :)

[JG1]

you could also use a lamp tree instead

[James77]

Just another option, and what i did for mine since my joists also did not line up:

I painted a 1x3 piece of pine the same color as the ceiling, about the same length as the fixture. I screwed that into the joists, and mounted the ATI to that.

If you do go the toggle road, which would definitely work....get the largest you possibly can. You can cover the larger hole using a fender washer( or the like) at the top between the top of the mounting nut and the ceiling.

[myerss]

Sounds like you gott it worked out.

[edsreef]

I wouldn't do it! Give it some of time, heat/cold/humidity extremes in the attic, house vibrations from wind, etc, and it will begin to sag the drywall and/or pull out.

IMO, you need to find a way to use the support of the nearby joists. My joists wer only about 2-1/2" from I needed to hang my fixture so I cut a small piece of flat alum bar stock and lag-bolted it to the joists then used a toggle nut/w stud to attach to.

[distractor]

This is exactly how I hang my lights and they are less than half than that dumbell.

[c0mp|ex]

This kind of surprises me as i've had my Current 36" Outer Orbit fixture hanging for 3+ years using just standard plastic drywall anchors. Wasn't aware that it was frowned upon.

[snulma1]

while that is an eye opening sag, your test only looks at single point load. If you are spreading the load equally and at a distance of (guesstimate!) 40" then you halve the point load, and it should not have as great of a sag.

[d0ughb0y]

I hung my fixture directly to ceiling drywall. The toggle bolts package will tell you how much load it can handle for ceiling mount and for wall mount, and the actual load it can handle is twice what it tells you. if you use two lines, then the fixture weight is divided between the two lines.

[Midnightsun]

The test is flawed unless you intend on hanging exactly in the center of the joists like you show. There is a huge difference the closer you get to the joists with your hanging points. Another flaw is the flex will be less in reality as the drywall is screwed in. In your test, the drywall can slide horizontally on the chairs. If the chairs were fixed and the drywall screwed to it, the deflection would be much less than what you see now.

Here is what I would do just to be safe. Cut a piece of 1/2" or thicker plywood which you can lay on top of the drywall from the attic. It should be able to fit between the joists so lets say 1" narrower. In the other direction cut it to suit your application. A single hanging point, cut about 12" plus. Double hanging points, about 6" wider than space between cables. Screw in from bottom through drywall and into the plywood and then do chin ups. :lol2: Well not really but at least there is no way in hell your light is coming down on it's own. :)

[mrbill24]

The test is flawed unless you intend on hanging exactly in the center of the joists like you show. There is a huge difference the closer you get to the joists with your hanging points. Another flaw is the flex will be less in reality as the drywall is screwed in. In your test, the drywall can slide horizontally on the chairs. If the chairs were fixed and the drywall screwed to it, the deflection would be much less than what you see now.


I'm also using 1/2" drywall with an unsupported length of 23" vs. 5/8" an an unsupported length between joists of 16" (assuming my builder followed code). The light I'm going to hang also weighs less than the dumbell(and will be spread out over 2 anchors). So in a super worst case scenario, the drywall holds a little over twice what it needs to. My 15lb cat has also been sitting right in the middle of the span as well. Maybe I will mist some water on the drywall and see what that does. It won't simulate years of high humidity etc., but I'm feeling pretty confident.

[Midnightsun]

I'm also using 1/2" drywall with an unsupported length of 23" vs. 5/8" an an unsupported length between joists of 16" (assuming my builder followed code). The light I'm going to hang also weighs less than the dumbell(and will be spread out over 2 anchors). So in a super worst case scenario, the drywall holds a little over twice what it needs to. My 15lb cat has also been sitting right in the middle of the span as well. Maybe I will mist some water on the drywall and see what that does. It won't simulate years of high humidity etc., but I'm feeling pretty confident.

With the info above, you will be fine directly into the drywall with toggle anchors. Do not mist your drywall. This will just make the exterior paper slightly wet and will prove nothing.

[tmichael]

A lot of good points here. I'm a Licensed Electrician and have mounted thousands of fixtures in the 13 years in the trade. If your not feeling confident in the anchors that the fixture came with head up to your local Home Dumpster(Depot) or Hardware store and buy a different type of Drywall Anchor. Try and find a Toggle that spreads open more after being pushed through the drywall. In doing so, the back side of the Toggle covers more surface area giving you more support per Toggle. The weight the toggle supports almost doubles when you go to the next size. Good Luck