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I live in an old house (about 90 years old) with plaster walls. I have all kinds of trouble hanging things up in the plaster, so I mostly just use 3-M Command strips whenever possible.

But there are a few things that are too heavy for Command strips, like very heavy mirrors or shelving. What is the best way to hang heavy objects in plaster?

I have an electronic studfinder, but (this is probably no surprise to readers here), it doesn't seem to work on my plaster walls. I've tried using anchors, but the plaster often crumbles when I drill into the wall. I've had problems, too, where I put the drill against the wall, turn it on and only a small crater is created - it doesn't drill through.

When I have to hang large objects, I just call a handyman. This is both expensive and embarrassing (I should be able to hang things on my walls myself!). They never, ever have any problems and nothing they've hung up has ever fallen or had any trouble of any kind.

What's their secret? I never thought to watch what they do, but they clearly have a simple, reusable system for hanging stuff up on plaster that I'm not aware of.

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  • 1
    Drilling plaster requires a bit designed for masonary.
    – Kris
    Feb 3 at 22:55
  • @Kris Even for an interior wall?
    – Bill
    Feb 4 at 11:38
  • Yes sir. Plaster is cement. Even when you are certain that a stud is behind the plaster a pilot hole through the plaster is important. Wood boring bits are not designed fir plaster.
    – Kris
    Feb 4 at 13:16
  • "What's their secret?" You should ask them. They know what they did and we do not. Can you look at the wall and see if they inserted an anchor or maybe see something that will give you a clue? I am sure someone here will share a secret or two.
    – Alaska Man
    Feb 6 at 23:01
  • When you say "anchors" do you mean something like Molly or toggle bolts, or some variation on plastic expansion anchors?
    – HABO
    Feb 7 at 2:17
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+50

Plaster and lath is really either fasten directly to studs (which can be difficult to locate) or cross your fingers with toggle bolts.

For fastening in the field, your best bet is toggle (or molly) bolts, but the issue is the bulging plaster. Once you drill your pilot hole (using an HSS bit, not a concrete bit, and never using hammer drill action), you'll need to do some patient twisting around until you find the flattest orientation available on the backside of your wall. Ideally you'll want to catch the lath entirely, but that's not always possible with a fat blob of plaster. Big box stores stock these bolts, and you will find options that carry as much as 450lbs load each bolt as fairly commonly available. Be careful though, your wall will likely support under 50 pounds at each anchor, no matter the anchor's potential maximium.

Vinyl (compression) anchors, as you have found out, are in almost every location going to be poorly suited to lath and plaster. These are not even worth trying, in my opinion. In particular, the compressive strength can split the lath and release sizable sections of plaster.

Another option, is to install a mounting rail between studs. Either recessed (which requires patching and painting) or surface mounted (less aesthetically pleasing that recessed and can cause problems with the projected reveal off the wall surface). This can be a board of whatever width strikes your fancy, but go for 1/2" thickness as a minimum bite for screws, then just fasten directly to the rail.

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I live in an old house too. I'll assume yours, like mine, has some history to it and has been renovated and altered over the decades. You can't do DIY in an old house the way you can in a new one. You can't follow simple repeatable rules. You have to learn how different walls are built and how different fittings behave. Your handyman's secret is experience and adaptability, and you need to develop that yourself.

In my house, some walls are plaster over lath, some are plaster over backing board, drywall over plaster, two layers of drywall over plaster, two layers of drywall directly on studs .... you get the picture? Yours may not have as much variation as mine but you'll have to learn what different materials feel like, learn what works in different kinds of walls, and you'll have to make mistakes and learn from them.

Let's assume most of your walls are plaster over wood lath. I've found that usually by drilling appropriately I can hang most heavy things (not shelves) on that. My "secret" ... Use longer screws than you would for drywall. Drill a small hole and feel your way. You can usually tell when you transition from plaster to lath. Keep drilling to see if you've got a stud. If yes, just use a 2.5" screw and you're good to go with anything. If you don't hit a stud then drill a larger hole into the plaster but not through the lath, large enough for a plastic anchor. Insert the anchor, which will stop at the lath, and cut off the excess. Then use a 2" screw. These are pretty strong and a couple of them will hold up almost any picture.

For shelving you have to find a stud. Sometimes a magnetic stud finder will find the lath nails but not usually. Sometimes it's just trial and error. Either drill lots of tiny pilot holes til you find a stud or drill a 1/2" hole and insert an endoscope to find it.

There is another solution: Don't hang shelves on your plaster walls. Buy standing shelves. Pretty much anything else can be hung safely by developing an understanding of how different screws and anchors behave in different materials.

One last bit of advice: Join the Facebook group "Historic Home Renovations" and share your questions and experience there.

Good luck!

EDIT: I should have added the possibility of a really good stud finder. There are new ones, quite expensive, that pair with a phone app to show you much more than a traditional stud finder can. I don't have one and haven't spoken to anyone who has used one successfully in an old house. Everything I know about them is from their fancy youtube infomercials, and of course according to those they can find a postage stamp hidden behind a concrete block wall. Or something like that. Maybe worth a try ... and you still need to get to know your walls to use one of those successfully, in other words they are not magic, but they might help a little.

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  • Good answer - monkey hooks can help you test a stud and you can cover the hole with toothpaste...
    – DMoore
    Feb 7 at 4:22
  • I don't think the monkey hook trick is useful in plaster. 1) You can't just shove it through the way you can with drywall. You need to drill first, at which point why bother with the monkey hook? and 2) you can't tell the difference between lath and stud with a monkey hook. The only way is to keep drilling.
    – jay613
    Feb 7 at 15:02
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You don't indicate exactly what you mean by "plaster walls". My house is plaster & lath and, in the nearly 30 years I've lived here I've mounted things simply by driving a screw and hanging whatever it is I'm hanging.

I've done this for everything from a simple paper-based 12-month calendar (OK, we put those on small finish nails) to a 6 foot long by 7 foot tall shelving system.

The shelves were metal stanchions secured to the wall with drywall screws every 2 feet. We put metal shelf supports on the stanchions, then particle board shelves on the brackets. These were loaded over the years with, primarily, paper products, so they were heavy. Note that "every 2 feet" was an approximation. We tried finding studs, but stud finders go nuts on plaster & lath walls because there's wood everywhere. We put the stanchions where we wanted them and the drywall screws, whether they hit only plaster, lath, or stud, held untold amounts of weight for nearly 30 years without the slightest hint of pulling out, sagging or damage to the plaster wall.

I consider it one of the benefits of living in a 19th century house - I own a stud finder, but I never have to use it.

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enter image description here Plastic Ankers work pretty well and can support the weight. Available in all Home Improvement Stores in different sizes

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  • No they don't, plaster and lath walls, not approved for this use. May 30 at 20:57

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