Eight inches. That's how far off-center my floating cabinet ended up after I hung it without checking where the studs landed. I measured the TV width, the cabinet width, the distance from the floor — but I didn't map the studs until after I'd already drilled the first hole. End result: a 48-inch cabinet sitting 8 inches to the left of where the TV actually was. I had to patch four 3/8-inch holes, re-prime, and start over. That's an hour and a half of work I could have skipped if I'd just done the math on the wall first.
Here's the mistake most people make: they pick the cabinet, measure the TV, and then try to center it on the wall visually. But a floating cabinet isn't like a shelf you can nudge around. Once it's up, it's up. If the studs aren't where you need them, you either end up with a cabinet that's off-center or you're forced into buying a shorter cabinet that fits the stud spacing.
Most floating TV cabinets I've seen are 48 to 60 inches wide. For a 55-inch TV, that width is fine, but the real issue is the stud spacing behind it. In most U.S. homes, studs are 16 inches on center, but the first stud from a corner can be anywhere from 12 to 24 inches away. So before you buy anything, grab a stud finder and map the wall. Mark every stud from the floor to about 30 inches up, and then decide where the cabinet has to go based on where you have at least two studs that align with the cabinet's mounting points.
I didn't do that. I just assumed the studs would be where I wanted them. That was the costliest assumption of the whole project.
Now, some people will say you can use toggle bolts and skip the studs entirely. Technically true, but a floating cabinet carrying a 30-pound TV plus a soundbar and a couple of consoles is easily 80 to 100 pounds total. Toggle bolts in drywall are rated for shear load, but they're not as reliable as a lag bolt into a stud, especially if the cabinet gets bumped or you hang something heavy later. I've hung Large Floating Shelves: What I Learned After Hanging 14 of Them, and I've had one pull out of the wall after a guest leaned on it. Not fun. So my advice is: don't skimp on the mounting. If you can't hit at least two studs, you might need a different cabinet or a wall-mounted TV cabinet instead.
The second thing I got wrong was the height. I hung the cabinet at 42 inches from the floor, thinking it would line up with the TV center, but I didn't account for the fact that the TV is wall-mounted and the cabinet sits below it. The gap between the bottom of the TV and the top of the cabinet ended up being only 5 inches — which felt cramped, and the set-top box I put on the cabinet blocked the TV's IR receiver. I had to move the TV up 3 inches. So measure the TV's bottom edge after you've mounted it, then decide the cabinet height. A good rule of thumb is to leave 8 to 12 inches between the bottom of the TV and the top of the cabinet for air flow and for cable clearance.
And I didn't check the depth, either. My cabinet is 16 inches deep, but the TV is only 2 inches from the wall. That means the front of the cabinet sticks out 14 inches further than the TV. It looks okay from the front, but from the side it's a ledge that catches my hip when I walk past. If your TV is mounted flush to the wall, you can get away with a shallower cabinet — 12 to 14 inches deep is usually enough for a soundbar and a console. But if you have a TV that sits on a stand, you need the cabinet to be at least as deep as the TV's base.
This brings up the whole TV Cabinet Furniture: Measure the Depth Before You Fall for the Width issue. Most people focus on width, but depth is just as important for a floating cabinet because you don't want it jutting into walkways.
Cable management was another blind spot. I ran the HDMI cables down the wall, but I didn't leave enough slack behind the cabinet. The cable grip on the back of the cabinet is tight, and I couldn't push the TV's HDMI deep enough without it kinking. So every time I adjust the TV mount, I have to reach behind the cabinet and unhook the cables. If I had installed a brush plate or a grommet hole in the top of the cabinet, I could have routed the cables through it. Some cabinets come with those pre-drilled — check before you buy.
One more thing: the mounting bracket. The cabinet came with a cheap, flimsy metal bracket that flexed when I put my weight on it. I replaced it with a 3/16-inch steel channel from the hardware store, bolted into two studs. That cost an extra $12 and took 20 minutes. Worth it. If you're planning to put a 55-inch TV on a floating cabinet, budget for a decent bracket. The one that comes in the box is often just for holding a light plant.
I've also learned to check the wall material first. In my last apartment, the wall was plaster over wire mesh, not drywall. My stud finder was useless, and I had to use the magnet trick to find the fasteners. That turned a one-hour hang into a three-hour headache. So if you're renting or in an older building, test the wall before you commit.
If you're still at the stage of picking a cabinet, here's what I'd do differently:
- Measure the TV width, but also the depth and weight.
- Map the studs with a good stud finder before ordering.
- Decide on the height based on the TV's bottom edge, not the floor.
- Check that the cabinet's mounting points can land on at least two studs.
- Buy a cabinet that either has a pre-drilled cable port or has a back panel that's easy to drill.
- Don't trust the wall anchors that come with the cabinet. Replace them with lag bolts.
I've also put together a guide on TV Cabinet for 55 Inch TV: What Fits, What Slides, and What I Wish — it goes into the fit specifics for common TV sizes and cabinet widths. And if you're trying to decide between a floating and a floor-standing cabinet, my Low TV Cabinet: What $150, $450, and $900 Actually Change piece covers what the price difference actually buys you.
My next project is a similar cabinet for the bedroom, and this time the first thing I'm doing is measuring the studs — before I even open the browser tab to order. That's my one concrete step for you: grab your stud finder, mark the wall, and only then start shopping. Your future self will thank you when the cabinet is centered on the first try.