To hold the studs to the walls, I located as many of the metal studs over the actual studs inside the walls. You can use a stud finder to find the studs on your walls if you need to. Unless you're sizing your hearth based on the studs in your walls, though, you won't be able to screw all of your metal studs directly to the studs inside your walls.
But that's okay, because 3M makes Command strips. Ha ha ha ha.
Mind you, the walls in this house are special: they have 1/4" OSB behind the drywall, which makes it easier to hang things without fear of having anchors pull out of the walls. Either way, though, there are several products out there which remove much of the difficulty of attaching even relatively heavy objects to a hollow wall.
To attach the metal studs which weren't located over a wall stud, I used two different types of wall anchors. First, I tried using EZ Ancor Toggle Lock anchors.
My attempts to use these were met mostly with frustration, though--the theory with these anchors is that the screw will hit a slanted metal tab on the toggle, which causes the toggle to turn so that it is perpendicular to the body of the anchor. For whatever reason, the screws kept bending the metal tabs instead of moving the toggle. Here's how that looked:
For reference, with the screw in place:
Frustrating, especially given that I'd had success with these anchors before.
Since that wasn't working, I went back to regular old toggle bolts. These standbys did the trick: drill a hole, insert the anchor screw through the metal stud you're attaching to the wall (an important step!), thread the toggle onto the screw, shove the anchor into the wall until the toggle pops out, and tighten.
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| Yup, the toggle is on there backwards. |
When all was said and done, the metal studs provided a nice, solid platform for the wall Durock to mount to:
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Click to enlarge: the metal studs with silver screws are held in place by toggle bolts. The studs with the black screws are attached to the wall studs. |
