I am working on installing wall-mounted shelves in my garage. To keep the shelves high enough that I don’t bang my head on them, I am finding I have to anchor the mounting plate up high on the wall, near the ceiling.
After installing one, I realized I am anchoring the top lag screw into the wall top plate.
The bottom lag screw in each mounting is low enough to be secured into a wall stud.
My head is screaming at me that it’s not OK to mount into the top plate but wanted to post to find out for certain. This is an exterior wall so I’d imagine load bearing?
Additional info that may be helpful:
This appears to be a double 2×4 top plate (see pic, the bottom 2×4 is seen in its entirety, with the 1.5” side facing the camera).
There are engineered joists above, running perpendicular to the top plate into which the shelf mounting plates are secured.
I’ve added a picture of the loading limit from the installation instructions. Circled in purple is the configuration I intend to use.
Thanks.
Best Answer
By mounting the wires into studs the back of the shelf is guaranteed to press evely on two studs
if you mount the wires into the top plates the back of the shelf may press against only ones stud and one corner of the shelf may burst through the drywall.
Remember that the the wire holds up the front of the shelf by converting the downwards force into a pull towards the wall.
This force is multiplied by the slope of the wire, so a fully loaded shelf could be pressing against the wall with 600 punds force at each corner.
So long as your wires (and shelf corners) are in line with the studs this will not be a problem asd the coners will then be pressing on the studs.
The top plate is if anything stronger than the studs. so anchoring to that does not make the shelf weaker.