Hey, I am about to embark on a permanent install of a center channel speaker, and TV mount to the wall above the fireplace in my home. The problem is, my house was built in 1928 or so, and I still have plaster walls (over wooden lathe). Anyone been in this situation before on here? Any concerns I should be aware of, or any limitations? I really don't want to trash my walls to find out ;)

Fasten your flat-panel and speaker mounts directly to wall studs, and not just to the plaster. If you were to use hollow-wall anchors to fasten to the plaster, you would stand a good chance of seeing large areas of your plaster fall off the lath.

As it is, you will need to locate and carefully drill pilot holes into the studs. Don't overtighten, as you might still cause significant damage to the old, brittle plaster.

Without seeing it, I'm not sure,.. But I've lived in a few places back in the day of similar dating. Plaster can crack and the crack spread.. and if it is significant weight, it can put tension across the whole wall if it has that. ( as well as just Pop right out)

I would suggest
1. Make sure you find the studs (some studfinders can do a deep scan, but with wood lathe I'm not sure how easy that will be.. but you GOTTA use the studs. Cant do it the same as drywall where spreaders and such can work)

2. I might even suggest cutting away a portion of the plaster and mounting plates (either wood, metal or even just drywall if you are still able to anchor to studs)to the area you are going to be mounting. That way if there is flex it wont be on the plaster. and if you dont want the look of plates you can use joint compound over it (if its slightly thinner than the plaster removed) and it will look the same after painting.

3. At very least pre-drill where the mounting bolts are going so the supports wont be putting pressure on the plaster.


Remember also that in houses built then, they often didnt standardize distance between studs like modern homes try to.

Good that you asked... cause to be blunt,.. yeah,.. you can EASILY trash your walls.
Plaster doesnt flex. so if it has tension, it can crack all the way across. and if not in a stud, can litterally pop right out...

I'm not a plaster pro, but I have dealt with what you are talking about... Taking time to do it right from the start is the key.. Dont just go by my suggestions ,.. get more, and try to be sure...

There are lots of variables here, but one thing you might consider is spanning a few sets of studs with plywood, spreading the load among those studs. Then, mount your bracket to the plywood. Some chimneys I've dealt with don't even have lathe & studs, you need to investigate exactly what it's all constructed from. You might be going to the brickwork of the chimney, and that's risky - that's when you start considering building out some woodwork to hide the wires, then recess the display & center channel supported by the woodwork.

This will also come into play with your wiring, both high & low voltage. What's your plan for that?

We had to do this in a landmark building (The Dakota in NYC) right after they'd re-done all the chimneys...it took more than two years to get the plans & inspections & architects' drawings & permit approvals & concealed wiring & patching & painting & custom casework done. Big fun, but maybe the pic will give you an idea what I'm talking about.

je

I mount shelving units, TVs, and display cabinets to my 1917 plaster walls all the time, but I always anchor into the studs for wall loadings over a few pounds. A stud finder works okay locating the studs, and I use anything from longish wood screws to lag bolts depending on the application. Always drill a pilot hole first slightly larger than the nominal diameter of the screw shaft (not the flutes). And as mentioned, do not overtighten or you will surely crack that plaster in the area of the screw.

Hey, I am about to embark on a permanent install of a center channel speaker, and TV mount to the wall above the fireplace in my home. The problem is, my house was built in 1928 or so, and I still have plaster walls (over wooden lathe). Anyone been in this situation before on here? Any concerns I should be aware of, or any limitations? I really don't want to trash my walls to find out ;)

I have one question. Why do you want to mount the set above the fireplace? If you're sitting a reasonable distance away, you'll have to look up and that can cause problems with the neck,etc.
Studies were done and the common rule was the center of the screen should be at the viewers eye level when seated if the sitting location was around 1 1/2 times the screen width.That generally means around 36-44 inches from the floor to the middle of the screen for the average person.
Food for thought.

When I'm reclined back in my recliner, the eyesight angle to my TV mounted over my fireplace feels about right. But then, with my increasingly bad vision, I guess I want to look out of the bottom half of my eyes as much as possible.

Find at least one stud. Lathe is a lot stronger than people here are giving it credit for, its not wallboard for sure. Most wall anchors do not work in lathe and plaster, so don't waste your time. Plaster is crumbly, so if you don't predrill, you will likely create a mess of a hole since it will put pressure on the plaster and crack it out from the screw. Putting a plywood mount up on the wall is not a half bad idea, since finding the lathe for a screw can be a hunt and peck situation.

dew.

dew, it's not that the lath is weak or strong. It's the fact that the plaster-to-lath joint is based on the lath not moving. Stress the lath, and the ground coat will lose its grip, when the 'locks', the bit that oozes through the lath, breaks off. Now the plaster is not firmly attached to the lath, and sections of it can fall off.

This is nearly 100-year-old plaster, and, if the ground coat is not 'on spec' for the mix, it might not be as strong as the general case, or, if it has been aged poorly, from heat or dryness, it can get crumbly. I have seen sections, multiple square feet, fall off the lath, by nothing more serious than a small child bumping into the wall, and this from not very hard an impact.

Hopefully the OP's wall are in the best of shape.

I've lived in a lot of places over the years, and plaster and lath walls are a royal PITA.

As mentioned, often the stud centers aren't standardized. Some walls, if they're short enough, may have but one stud; I wanted to put some cabinets on the 45" long wall above my desk (house built in 1941), but there's only one stud in it, 12" from the left side, and nothing on the right.

You'd be surprised how often even old-fashioned "craftsmen" cut corners back in the day.

I'm an electrician thats worked in mostly old houses. The trick to finding a stud in a home that has plaster and lath is to use a stud finder with metal setting. When you find a stud, the lights or indicators will flash as you move the detector vertically because of the nails used to nail the lath to the stud.

Quick Questions. What type of fireplace is it? Is it true brick and masonry or is it a facade with piping? (so my current is a facade. The back side is built out with studs and it is just an open cavity with piping going up it even though it has brick on the front)

If it is a facade, you "should" have studs bracketing the fireplace to frame it.

If you have true masonry or brick,.. then you should be able to mount to it.. Though that is a different animal and needs its own consideration.

But either way, I think you are going to be able to do it.. Just take plenty of time figuring out how you wont be putting tension on the plaster.. especially the TV, as those can be pretty darn heavy and often set out a bit putting even more torsion on the mounts..

You don't specify how heavy the TV and speaker are. That has a huge affect on whether or not this is practical. Personally, I would not trust studs from 1928 to hold an expensive TV. I would want to open up the wall and do some reinforcing.

But as someone else said, think twice (three times even) before investing the time on putting the TV above a fireplace. Whenever I visit someone with a TV placed there, I find it very uncomfortable and unnatural.