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Repairing plaster walls and attaching things to plaster walls are discussed in this audio episode of The Handyguys Podcast.
The Handyguys received this question from a listener:
Would you please talk in detail about homes with plaster walls? I have never lived in a home with plaster walls until now and have only heard horror stories about putting things/pictures, etc, up on the walls. Can curtain rods be hung on plaster? Is it best to live with and/or “enhance” the cracks as a feature, or can they be fixed for a reasonable amount of $$? LOVE YOU GUYS! Thanks!
No horror stories here. Some cracks might be inevitable but we discuss in the show doing repairs and hanging things on your plaster walls.
Types of plaster walls
Traditional plaster are often made by installing strips of wood lath to the framing and then multiple coasts of plaster are spread over the lath. The plaster can contain pig hair or horse hair for strength. This may also be applied, in some instances, over a masonry, brick or stone wall.
Modern plaster, also called veneer plaster, is installed over a substrate board, similar to drywall.
Hanging things on plaster walls
Paul had good results with what he calls “tempered picture hanging nails” or also called hardened steel picture hook nails. You can get these at your local True Value hardware stores. Make sure you read the package for how much weight the particular hook can hold.
You can also use a screw into the lath or a stud. A trim head screw would be ideal but other screws could be used as well.
How about curtain rods? YES, you may be able to install the curtain rods with the hardware provided. If you are installing heavy curtains, you will want to use a longer screw than may come with the curtain rods and then make sure you screw through the plaster and into the framing around the window.
If you are attaching heavy things like shelves, and you can’t screw into a stud, you may want to use a Toggle Bolt. These expand behind the wall to provide good holding power but will need a larger hole to install them.
All of these attachment methods assume your plaster walls are in good shape. What if they are not? Then you may have to repair the plaster before attaching anything to it.
Repairing plaster walls
There are a few types of common repairs; cracks, missing pieces or separated lath and plaster. The repair method will vary depending on what type of plaster you have and how it was originally installed.
Repairing plaster separated from lath
If the plaster has separated from the wood lath, it’s likely because the “keys”, where the plaster connects to the lath, have broken off. You need to re-attach the plaster to the lath. This can be done with drywall screws but a better solution would be to use “plaster washers”. These washers are either metal or plastic. They are about 1 1/2″ wide, a screw is inserted through the washer and driven into the wood lath. The washer pulls the plaster tight against the lath. You will need these washers every foot or so (or every few inches depending on how bad the plaster is detached) to secure the plaster. Once the washers are installed, and the plaster is stabilized, you then skim a coat of new plaster over the washers to hide them.
Repairing cracks in plaster walls
It seems that cracks in plaster are sometimes unavoidable in old homes. These homes will move with the seasons and cracks will re-appear over time. A traditional approach to repairing cracks involves removing any loose plaster and then filling the crack with new plaster, also using some paper or fiberglass joint tape if the crack is large will help. If the house does move a lot then there may be little that can be done to keep the crack from re-occurring.
If the crack is small, Paul suggests just using a flexible, paintable, caulk in the crack. The flexibility of the caulk gives you a better chance that it will stay put and the crack will not re-appear. If that fails then you can try the more traditional method down the road.
Repairing holes in plaster walls.
For repairing a hole in a plaster wall Paul recommends “Patching Plaster”. It’s a fast drying plaster than comes in small containers for small repairs. Check it out and follow the directions on the package.
Tools for plaster repair
You will only need some basic tools and supplies for repairing plaster. You will need a 6″ wide putty knife and a 12″ wide knife, your plaster washers, a utility knife, some paper repair tape and a container to mix the plaster in. These can all be found at your local True Value.
We were one of the bloggers selected by True Value to work on the DIY Squad. We have been compensated for our time commitment to the program as well as our writing about our experience. We have also been compensated for the materials needed for our DIY project. However, our opinions are entirely our own and we have not been paid to publish positive comments.
I run into this problem a lot I will try the ‘patching plaster’ next time. Thanks for the recommendation.
You’re welcome.
Unfortunately we see the problem a lot as well. Even worse is when we see homeowners who have tried to correct it themselves and only made the crack worse.
Thanks for the tips, I have this problem at home and every time I tried to repair it, it makes the crack bigger. I guess I’m doing it wrong.
Hi
I’ve just had a guy to plaster a new extension to my old house.
The guy plastered the new erected walls and its showing horizontal like crack lines .
Question:
How do I fix the problem
Well, first thing I would do is contact the guy who did the job. I would expect him to stand behind his workmanship. But, if the walls were not build correctly, had movement in them, then it may not be his fault.
It depends where the cracks are and how the plaster was installed. Was it a plaster veneer over blueboard? If so, does the crack follow the seam of the board?
I would need more info, how the wall was built, how the plaster was installed (what type of substrate) and where the cracks are. Perhaps you could email pictures to [email protected]
I am trying to replace a toilet paper holder and the hole in the plastered wall is too big. HOw can I get the screw to hold in the wall?
It depends how big the hole is. If it isnt tooooo big try using a toggle bolt instead of the supplied screws. If that wont work let us know.
I have a hole in my plaster wall where I need to put a curtain rod how do I fix it to hold rod
Maybe you can get a piece of wood into the hole, and attach it with a couple of screws in the existing plaster or drywall. That will provide a backer for the new joint compound or plaster and give you something to anchor the rod bracket to.
I’m having a problem with a plaster ceiling. I have a spot where the 1/8 finish plaster is seperating from the rough plaster. I picked as much as I dared out (about a 6″x8″ area) and filled with joint compound and that promptly cracked and wasn’t attached. So I’ve dug it out again.
The screws holding one of my railing brackets to the plaster wall have pulled out of the wall. How can I repair these so the screws will hold safely?
I would try to determine where the stud is in the wall (use a stud finder perhaps) then move the railing bracket so your screws can hit the stud. Make sure you use long enough screws to go through the plater, lath and well into the stud. If you cant move the railing bracket and use anchors I would use toggle bolts. The best solution is to move the bracket and not use anchors at all.
could u tell me how to hang old barn wood over plaster walls
Jill – That sounds like a great project! Nails would be the most authentic way to hang it. Use a stud finder to locate and mark the studs on the wall then nail them up. For an even cooler look you might want to consider old fashioned nails. Here is a link to some antique looking nails at Amazon.
Antique Nails
Is laminating over the plaster with 3/8 drywall a good idea, together with the plaster fastners?
It depends what you are trying to do. If your walls are significantly cracked in many many places – Yes, many people will do the 3/8″ drywall over the plaster. No need for the plaster fasteners, just use long enough screws to reach the studs. The issues will be…
1) you will need electrical box extenders.
2) You will need to remove window trim, door trim and baseboards.
3) you will need to extend the jambs on windows and doors.
4) reinstall window and door trim.
5) When you re-install the baseboard you will need to trim it because the room is now smaller.
Its a big project but will revitalize a room with really bad plaster.
I’ve read tips on plaster repairs on several sites. From my own “in store” searches I ran across a product that hasn’t been mentioned on line. That is a liquid for painting onto the old plaster BEFORE applying the new plaster compound/patch. Don’t recall the name, now, but it seemed to be a standard, almost generic liquid sealer for plaster. Basically it is a milky fluid that can be painted directly onto the “old” plaster, or diluted a bit with water depending on the project. This is well explained on the bottle.
The product amazed me by soaking well into the old plaster, penetrating it. Once it sets, even the loose particles of plaster, that survived the cleaning and preparation of the hole, were now anchored to the wall. This new conglomerate medium looks like wet plaster (my wall’s plaster had lots of sand in the original mix) but is the consistency of gummy candies (but “candy” loaded with sand)! The patching compounds should be applied before the prepared area has totally dried, because it remains tacky for awhile after it first sets up. It seems to also improve the old plaster’s adhesion to the lathe. Once I saw the holes prepared this way I felt much more confident in the repair — even before I’d applied the patching plaster.
I live in a neighborhood with a lot of hills. All the houses here move because of the terrain. I tried the paintable caulk about 20 years ago. It looked “okay” at first, but over time it has shrunk and there are depressions following the line of the crack instead of a smooth finish.
You can’t fight the house – so paintable caulk was the right idea. And there are no cracks 20 years later. However, because of the shrinkage it looks like crap now.
Looking for something that you can slap on like spackle or plaster but is rubberized so you’re not fighting the building. Any ideas?
Nothing comes to mind. If you got 20 years from the caulk….. Maybe try that again.
I have a hole in my bathroom where the shower curtain rod rubbed through what looks like 3 layers of stuff. The shower rod is not a permanently installed one therefor it has been moved back and forth till it made a hole. I’m a single parent trying to do repairs that my ex refused to do. And am not familiar with some of the terms people use. The hole is 6 inches wide and 1 inch tall. Any suggestions?
Use paper or fiber joint tape and drywall joint compound. You will need a 6″ putty knife and some sanding blocks. Step one, embed the tape in the mud and cover the hole. It doesn’t need to be super neat, just get the joint tape flat. Let it dry. Knock off any high spots with the sanding sponge and apply another coat of joint compound you will want this to be twice as wide as the tape as neat as possible. Let it dry. fill in any low spots and cracks and let dry. Now sand everything to blend it in with the surrounding wall. If needed, another thin light coat of mud and sand again. then prime and paint the wall. Good luck!
We need to hang a heavy mirror on the wall, weighs about 40lbs. Do we need to hit a stud? How do you find a stud in plaster walls?
Yes, I would find a stud. Try a good stud finder, or a really cheap one. The cheap
in them are often the best type to use with plaster walls.
stud finders that have a magnet
Hey guys,
I’m trying to mount a tv bracket on a wall that I believe has been plastered directly on a stone wall. This plaster was then covered by a layer of drywall.
Any suggestions?
Thanks,
Josh
wow – the key thing here will be to anchor in the stone wall. There is no way of knowing if the mortar between the stones is solid. Often a stone wall is plastered over due to deteriorating mortar joints. regardless, there is no way of finding those mortar joints. You will need to drill with a long enough masonry bit into the stone and use a suitable anchor. I think I would probably go with a Lag Shield or with a wedge anchor. You will need to use a masonry bit with a hammer drill to do the drilling. You could end up needing a few masonry bits of the stone is especially hard. Here is a link to a show about hammer drills
50 years ago (!), I mounted a punching bag with a heavy wooden frame and backboard to our basement wall. No mortar to deal with in this case, but the concrete foundation was just a few years old, and very hard.
Hammer drills were a specialty item then, and even today, I would try the method I used back then (when I was 15). That was a masonry cold chisel with a very hard tip that was shaped a bit like a philips head screwdriver. It was essentially the “manual” version of the hammer drill. The chisel was about 14 inches long, and while holding it firmly against the concrete wall, I hammered it over and over; all the while turning the chisel shaft left and right (clockwise, and counter’). For my purposes I chiseled holes about two inches deep, and inserted anchors with expansion wedges in the end that was inserted into the wall. A few solid smacks on the anchor, pushed the wedge into the anchor so it spread and became one with the wall. I beat on that punching bag for hours with my family upstairs hearing the wood frame resonate with every punch. The mounting never seemed to give an inch.
Without the “manual” chisel, I never would have been able back then to afford renting the right drill. Oh, and the ONE chisel was up to the task and showed little wear after the job was done.
Mike – Great story! yes, I forget about the old fashioned way of doing things sometimes. Here is one
Thank you, Handy guys!
Yes, that’s a photo of just the tool I was writing about.
Nice of you to acknowledge my little tale…
My dad prompted me to use the chisel, drawing on HIS dad’s career as a builder. We still visit the stone church that Grampa and his brothers built in Tacoma, Wa.
~Mike
And a word of caution. Not only do they put horse hair in to help bind the plaster, but in my house they used asbestos. If you have an older house, it may be worth while to get your plaster tested before making any major changes that result in damage to your plaster.
what is the best method to install door and window casings when you have plaster walls?
Nails into the framing, through the plaster.
Want to “glue” one plaster vent to plaster wall. What should I use? I would like a small tube of glue or pre mix whatever and not have to buy a big packet or bucket at bbig prices.
If it is indeed connecting plaster to plaster. I think a traditional method is with plaster! Plaster here http://amzn.to/2dEkyu3 and use a bonding agent http://amzn.to/2dMzYg2 if its not raw plaster. You would want to use tape or something to hold things while the plaster set.
if you dont want to go that route. Perhaps something like a high initial tack construction adhesive would be easier for ya. http://amzn.to/2dltau9
I stuck 4 strips (each ~30cm long) of masking tape at equal intervals along the outward face of the plaster vent so that there was ~7.5cm overhang on each side to later secure the vent to the wall. The vent was then laid flat face down on a flat surface. I then applied Selleys liquid nails fast grab high strength to the back border region of the vent. I then pressed the vent in position onto the wall and secured it with the overhanging masking tape. I then also ran a strip of masking tape horizontally along the base of the vent and the wall to give extra hold. The other previous strips were in vertical orientation when the vent was in place on the wall. After 72 hours I gently removed all masking tape. The vent is holding in place.
I would like to put barn type boards on a wall that has been plastered..Can I do this with long screws or what should I use?
Hi Nancy – I love that look! Yes, screws work nicely for this project. Nails can work too. If I’m using screws, I would use #6 “Trim Head” screws like these. http://amzn.to/2oiksx8 I would make sure they are long enough to go through your barn boards, through the plaster and lath and into the studs. If your board is 3/4″ thick I would make sure the screws went into the studs 3/4″. If you lath and plaster is 3/4″ thick then you would want about 2-1/4″ long screws (longer is okay). Here is an example http://amzn.to/2onnT4Q
If I’m nailing – I would use a 15g or 16g pneumatic nailer, again, nailed to the studs.
I would also paint my walls black first. If you do this you wont see the wall between your boards if they are only butted together.
Hi I am trying to attach a closet installation made out of industrial pipes (example link below) that stands on the ground but needs to be attached to the wall up top for stability, it will hold about 200 lbs of clothes, but is stable. What is the best way to do this on plaster walls? Thank you!
visual examples of my installation: https://www.pinterest.com/explore/pipe-closet/?lp=true
The absolute BEST way would be to just use screws or bolts directly into the studs. The issue may be, the studs do not line up with your pipes. if that happens just run a board horizontally the entire length of the shelf. use lag bolts or deck screws to attach that board to the wall, into the studs, then just screw the pipe flanges into that board.
So I have plaster walls in my kitchen with paneling glued to it. Think 60s ugly yellowish e Brown swirls. Anyway I want to take the paneling off and put up shiplap style boards. It’s really thin plywood cut into planks. Can I glue them to the wall or should I use small nails. I don’t want to see nails. TIA!
You should nail into the lap on the shiplap so the nail is covered by the next board. Nail into the studs, through the plaster. A nailgun makes this very easy.
Hi! I am in the process of repairing 6×12″ openings in a plaster wall from removed vents. I’ve used patching plaster to fill the holes and sanded. Is a skim coat of the compound necessary? I do have All Purpose Drywall Compound with a green top (can’t recall brand, off top), is that the right product? Also, is a water-based primer necessary or will a primer + paint in 1 work? I have Bullseye Vissner (?) Water-based multipurpose primer.. will that work? The directions on that say to wait 30 days, but is that a must just for patchwork? Thanks for any input!
No skim coat of drywall compound is needed if the patching plaster gave you satisfactory results. If you do topcoat you can use the green lid stuff or blue or mix up some quick set. Primer will help you use less of the more expensive top/finish coat of paint. Often drywall primer is PVA primer and dries very quickly. Bullseye primer should dry very quickly too.