I want to mount bookshelves on rails in my office. My office manager says that the walls are "drywall on steel studs" on one side; plaster and lathe over "thin steel studs" on the other.

What are my options for mounting? I assume I want to screw directly into the studs - but with what? Just a standard screw? Togglebolt? Note: I am in earthquake country (California).

This is sort of what I want to do:

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  • 1
    DIY is lovely, but this is commercial space with it's own set of responsibilities and liabilities. Suggest you either get a pro with license/insurance, or opt for free standing units (anchored, of course, for when the quake hits). Feb 25, 2016 at 13:54

4 Answers 4


There's no such thing as a "standard" screw. Every type of screw has a particular purpose. In this case you do want to screw into the steel studs, and therefore you want a screw with a thread pitch and depth to suit. Most screws provided with shelving systems are better suited to wood studs.

The first problem that you're likely to encounter is that the "standards" (vertical rails) are usually countersunk to accept a small #6 or #8 flat-head screw, which is a bit on the small side for a massive stack of books. The second is that they system in your photo appears to only be supported every 32 inches. That may not allow enough anchors to be used.

If you 1) use all available screw holes, 2) install standards on every stud (which means using a shelf system that has brackets every 16 inches), and 3) use the largest sheet metal screw that fits behind the shelving you're using (#8 or #10), I think you'll be successful.

  • I assume i should drill pilot holes for the metal screws using something like this chart: frentzandsons.com/Hardware%20References/…
    – RoboKaren
    Feb 24, 2016 at 22:31
  • Most sheet metal screws are either self-piloting (really sharp) or self-drilling (having an auger tip).
    – isherwood
    Feb 24, 2016 at 22:49

Firstly you need to find out of the steel studs are strong enough to support the books.

If there are, you will only be able to put the uprights where a stud are, that may not be where the shelving systems needs them to go.

Personally I would be looking for a set of free standing shelves, so the wall does not have to take the weight.

  • 2
    How would a person find that out?
    – isherwood
    Feb 24, 2016 at 22:50
  • 1
    I go along with using shelves that sit on the FLOOR.
    – Michael Karas
    Feb 25, 2016 at 4:13
  • @isherwood, That the point, it is very hard to find out how much steal studs will support, as you don't know how they are fixed etc. THEREFORE personally I would be looking for a set of free standing shelves.
    – Walker
    Feb 25, 2016 at 14:14

I did a similar setup for my bedroom recently. #12 sheetmetal screws along the top of the rails, and #7 fine-threaded drywall screws through the rest of the upright standards. My shelving is more decorative than practical, however. I definitely would not rely on my walls to hold up a heavy metal drawer system full of papers. I have some toys, plants, paintings, etc. on it.

One thing to consider is: what are your floors and ceilings made of? While houses tend to use thick wooden studs, which makes it easy to mount things directly off a wall, newer high-rises with steel studs often get a great trade-off for strong walls with strong concrete floors and ceilings. You won't be able to fasten anything against some styrofoam drop-ceiling, but concrete above and below a shelf on tension rods could hold all this easily. It's a similar style, and extremely strong since obviously a concrete floor & ceiling aren't going to yield under a few books.


I agree with Walker & you. Seriously, go only with a self-supported floor standing system & you're absolutely right with the Toggle Bolts through the steel studs for just anchoring everything to the wall.

Steel studs are incredibly horrible & the only thing that gives a false sense of security is Coarse Threaded screws. Any, fine or shallow threaded screw will strip right out of steel studs, coarse threads will only hold a little longer but once they flare the metal & break free they slip right out too.

Relying on screws in steel studs for a stronger earthquake zone is a bad gamble, it's just a matter of time once they've started to work free. On a beautifully perfect day with no weather or seismic events people with compromised screws in steel studs will have even their Drywall dropping & falling off like it was nailed-in when the trash truck goes rumbling by.

  • 1
    This is the opposite type of screw to use. A 4x8 drywall panel is about 100lbs, and is held up with fine threaded drywall screws, not coarse. Coarse is for wood studs. You'll have ~16 of them (#6's) per panel, and they can stay on the wall securely without falling off. Does that mean I'd put a heavy dynamic load up against them, like metal drawers full of paper? Probably not. But they're pretty strong on their own, though you do tend to need to use many smaller screws, vs a wood stud where you use a few big ones. Feb 1, 2018 at 22:39
  • My own testing disagrees. Fine thread should not be used anywhere ever, they're total garbage (before steel studs existed) and pull-out like any nail....coarse thread does not. However, none of that matters, I frowned upon the reliance of either for this shelving situation.
    – Iggy
    Feb 2, 2018 at 15:51
  • I'd challenge you to find any authoritative source that says coarse threads should be used on metal. Fine threads are for metal, coarse for wood. Feb 2, 2018 at 16:39
  • 1
    You're entitled to your opinion. But, authoritatively and factually, coarse threads are deeper than fine threads and coarse threads bridge the steel stud's thickness and don't deform and weaken the steel stud's hole like fine threads do. Try it like I did and you'll see. Again, fine thread came long before steel studs and they were never "made for them".
    – Iggy
    Feb 2, 2018 at 16:49
  • good read: contractortalk.com/f49/… Feb 2, 2018 at 17:15

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