holding power of metal vs wood studs

I'm mounting some shelving (channel and bracket) into a wall with metal studs, which I've never done before.

what is the difference in holding power of metal vs wood studs? are different screws recommended? or should I use toggle bolts in the drywall?

tia,

jc

Reply to
Joe
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The metal folding / expanding bolt anchors sometimes called "mollys" installed through the studs work well. You have to be careful to drill through the stud edge without pushing too hard and bending the stud flange.

Reply to
Pete C.

Usually if a builder knows they are hanging something they will put wood blocking behind steel studs because they are not particularly good for hanging things on. The moly bolt idea is probably better than sheet metal screws but be careful drilling. If you hit a piece of Romex you could end up with shelf brackets with 120 volts on them. Steel studs are not bonded/grounded unless you live in Florida and you have a new house (2007+)

Reply to
gfretwell

If there are metal boxes attached to the metal studs, the studs will, by being in physical contact, be grounded. If you have plastic boxes, they will not be grounded. One of the many reasons that I do not like plastic boxes.

Reply to
EXT

It depends on the thickness (gage) of the steel stud material. Heavy gage (16 ga or better) steel studs are very strong & I would trust them to hold a screw quite well.

Lighter gage (like 30ga) steel studs can be kinda wimpy.

I would suggest sheet metal screws of minimum size of #10 and a coarser thread. Drill hole in the stud flange just slightly smaller than the screw root diameter. A smaller hole will allow the screw to "upset" the stud material and form somewhat around the screw, This will give better screw holding behavior.

Molly toggle bolts are another way to attach to (through) steel studs or to the drywall but I find them somewhat of a PITA to install and require huge holes. Additionally removal means losing the toggle.

How strong are the shelving channels? How heavily are the shelves going to be loaded?

cheers Bob

Reply to
fftt

It depends on the thickness (gage) of the steel stud material. Heavy gage (16 ga or better) steel studs are very strong & I would trust them to hold a screw quite well.

Lighter gage (like 30ga) steel studs can be kinda wimpy.

I would suggest sheet metal screws of minimum size of #10 and a coarser thread. Drill hole in the stud flange just slightly smaller than the screw root diameter. A smaller hole will allow the screw to "upset" the stud material and form somewhat around the screw, This will give better screw holding behavior.

Molly toggle bolts are another way to attach to (through) steel studs or to the drywall but I find them somewhat of a PITA to install and require huge holes. Additionally removal means losing the toggle.

How strong are the shelving channels? How heavily are the shelves going to be loaded?

cheers Bob

Bob,

Thanks. The shelving chanels are the double row type. I'm going to assume worst case for the load (books).

jc

Reply to
Joe

Joe-

Oops! I typed 30 gage but I meant 20 gage as the example of thin stud material......I think the thinnest steel studs are like 22 or 24 gage....maybe 26?

I'd sure like it if they just went to .0xx material thickness & stopped using gage. :(

Anyway...if your channels are very stifff and act like a long "strong back" (4', 6' or 8') mounted to the wall, then the withdrawal forces on the screws (the ones at the top) would be much less than if the channels are short & flexible.

cheers Bob

Reply to
fftt

Uh, I don't think the trade name "Molly" was ever used for toggle bolts. Your complaint is true of toggle bolts, but not of Mollys (expanding fasteners), which remain in place when you remove their screws.

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Jeff

Reply to
jeff_wisnia

Jeff-

Sorry about calling toggle bolts "molly toggles"......its nod to my dad's terminology of 45+ years ago. and I sometimes slip up & use his term "molly toggles" interchangeably for toggle bolts.

I'm not a fan of either toggles (huge hole & sloppy installation) or mollys (a PITA to install & leave a chunk of metal in the wall) but when one is dealing with drywall the options are limited. :)

Since steel studs have a fair amount of strength, I use coarse thread larger diameter (like #12's) metal screws. With a decent shelving channel they should work just fine.

cheers Bob

Reply to
fftt

Quite true. But many/most condos require armored cable.

We have steel siding on our house. There is no deliberate "bonding" of the siding but it seems to test out as a very solid ground. Thing is that the steel systems are quite well bonded to each other. Just the casual contact with "real" grounds seems to do a good job. A few months ago I put up some of that aluminized "bubble wrap" stuff as insulation. (This was a wood frame house.) I accidentally let some of the "bubble wrap" come in contact with a hot wire. If I had not been "right there" it would have been fun to watch! Anyway, it defintiely tripped a 15 amp breaker. The house is a mix of metal and plastic boxes but I still have no idea how the "bubble wrap" got bonded but there is no question that it was/is.

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Reply to
John Gilmer

Most of the strength of a metal stud wall comes from the drywall material. Just don't impose a load that would cause the drywall to fail.

Thus, it's best to just anchor into the drywall material.

For my money, "molly bolts" suck!

I have had very good experience with the plactic anchors that "pop out" in the cavity but even the sleeve type plastic anchors are pretty good.

Toggle bolts always work.

Reply to
John Gilmer

That would depends on what the shelf is going to hold. Not for heavy books, IMO.

Reply to
Ed Pawlowski

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