Stud seems too shallow, what is going on? is mounting a TV safe?

Question

I am mounting a TV above my fireplace and I am getting a bit anxious about the stud we are going to attach the mounting system on to.

After struggling for a while to find the stud we used a thin nail to measure where the center should be, and found that the stud was at least 2 1/2 inches wide! we drilled in, and all seemed normal, but our drill bit (which extends 2 1/4 in) felt like it got past the wood (only for the last 1/4 inch or so). Is it possible this stud is wider and shallower than the rest? Is there a non-invasive way to test it? I am mounting a TV thats about 20lbs. The wall mount is a full motion one, can't tell how much it weighs. Is this "weird stud" likely sturdy enough to mount the TV on? Is there a way to tell for sure?

Answer 1

It sounds like the stud is mounted sideways. Instead of 1.5" wide and 3.5" deep, it is 3.5" wide and 1.5" deep. That is not generally a good idea for regular framing. But it is quite common if a non-structural wall is built in front of a brick chimney over a fireplace, as cuts the total additional wall depth needed from 4" to 2". Absolutely normal and perfectly fine for supporting a TV.

There are two other potential issues to consider:

• Height - Above a fireplace often means much higher than normal viewing height, which may be a little uncomfortable, depending on the size of the room, type of seating, etc.
• Heat - TVs and fireplaces really don't get along. If the fireplace is for show only then this is a non-issue. If you plan to actually use the fireplace then I would seriously reconsider the location of the TV.

Answer 2

How thick is the wall?

It "flat framed" with 1.5" by 3.5" studs flipped sideways, to leave more room for the chimney. Or you are seeing a double stud, which is two 1.5" studs next to each other.

Either way, 20 lbs is quite light, and I would not worry at all about it.