Help with plaster walls, please.

Need advice, technical help or opinions, you will find plenty here! (Technical posts here)
User avatar
Manalto
Inventor of Knob and Tube
Posts: 2114
Joined: Tue May 16, 2017 11:09 pm

Help with plaster walls, please.

Post by Manalto »

This question has been rattling around in my head for a while now and no "a-ha!" solutions have come to the surface.

What should I do about my plaster walls?

I don't want to cover the walls with plasterboard. (Let me take a moment to say that, although I don't watch much TV, I assume this must be the HGTV solution, judging by the knee-jerk suggestions made by nearly every visitor to my house, those same people who, unsolicited, advise me to install replacement vinyl windows.) For this 100 year-old house, the walls don't need to be perfect. I like the gritty texture of plaster and don't want to lose that. I don't mind slightly greater irregularities either, although I would like to find a material that I can use to better blend damaged spots with the surrounding wall. I don't even object to cracks in the plaster. I have repaired two deep cracks that ran the height of the room in two corners, but the remaining cracks are minor and don't appear to be in danger of letting go; in fact, I like the character of an honest crack or two in the walls. (Sorry, Bonnie, if you're reading this, you're probably on the verge of apoplexy at this point.)

The multiple layers of kitchen wallpaper have come down without a problem. There are a couple of areas where there had been damage to the walls and the repair was crudely done. I discovered, when putting down the floor leveler, that this stuff has good adhesion and when partially dry and thick, works well as a patch, matching the texture of the surrounding wall. However, this random discovery may be reinventing the wheel; is there something I can use that was formulated for this purpose or should I just go with the floor leveler with its gritty texture? I plan to paint the kitchen walls. (There's a little nostalgia here; my grandparents' kitchen had painted-plaster walls.) I'm determined to get the wood trim flawlessly smooth - or as close to perfect as possible. My thinking is that irregularities in the wall, contrasted against neat, crisp, glossy trim, will be a good look.

The rest of the house isn't so simple. The problem is where wallpaper has been painted and this combination has stubbornly adhered itself to the plaster. In some areas, no amount of scraping will release it; in other places, it flakes off the plaster easily, the result being a patchwork of irregularly-shaped blotches on the wall, smooth where it's painted wallpaper and rough where it's raw plaster. I know I can scrape the walls and remove everything that comes free, and then wallpaper over it. I've begun the process of using a 'Paper Tiger' puncture tool and hot water with zero results. I haven't rented a steamer yet; I was told that a steamer, if not used carefully, could soften and release the plaster. Many years ago, I sponged four shades of the same color in the hallway of my apartment. It looked great, and the effect was subtle. I don't think, however, that I want to do an entire house this way. I cringe at the thought of the 'shabby chic' aesthetic; I think this trend has done a lot of damage, although I'm not ruling anything out. Do any other suggestions come to mind? What would you do? (other than apply drywall)

User avatar
GinaC
Forgotten more than most know
Posts: 437
Joined: Sat Jan 26, 2019 8:19 pm
Location: Newport, VT

Re: Help with plaster walls, please.

Post by GinaC »

I'm new here, so please forgive me if I post something that has been discussed before and dismissed as less than ideal.

If you're saying that you want more plaster-like texture on the walls, perhaps you could try something like this: https://www.behr.com/consumer/products/ ... an-plaster
1939 Minimal Traditional

User avatar
Manalto
Inventor of Knob and Tube
Posts: 2114
Joined: Tue May 16, 2017 11:09 pm

Re: Help with plaster walls, please.

Post by Manalto »

Thanks, Gina. If this product has been discussed before, I didn't see it, so thank you for the new-to-me information. This may be just the ticket for my issue of irregular walls. I realize my "question" is more like a rambling description of my situation, but I don't really know how to articulate the question yet since I don't yet know my goal exactly. My hope was that someone who has had the same issue or experience with stubborn painted wallpaper would have a suggestion. Your answer was helpful.

phil
Has many leather bound books
Posts: 4616
Joined: Tue Aug 18, 2015 6:11 pm
Location: Near Vancouver BC

Re: Help with plaster walls, please.

Post by phil »

the paper tiger didn't work for me either.
close up the room , get it really humid in there. you probably have one of those pressure canisters for fertilizing plants, squirt the walls with it. you can add a bit of alcohol if you like. It reduces surface tension.

plaster can take water. It will not redissolve. dont; be a afraid to get it wet. I just brought the hose in the house and used the sprayer.. you might tape up the electrical outlets,, remember water and electricity don't mix. shut off the breaker for the room.

instead of the paper tiger, try making horizontal cuts with a box cutter. go at an angle downward, you want the water to creep behind. try not to go into the plaster but if you nick it you can fix that later. this will give a place for the water to bleed under the wallpaper. if you like tack some old towels to the wall to hold the wet against the paper. the trick is to get the paper wet enough keep it wet, then it just lets go. You'll do less damage than if you scrape too much and stress over it. you can use a steamer if you like but the secret if you are struggling is more water. boil a kettle in the room. make it like a sauna the plaster walls can take it. the paper wil want to fall off once you get it wet behind the paper and paint. If there are more layers you can do them all at once.

don't be surprised if you have calcimine paint, if you do I'd use hot water mop and bucket and keep changing the water until no more comes off. calcimine paint is water soluble and it redissolves unlike latex. it was used back in the day as a first coat because fresh plaster didn't take regular paint well until it was cured a few months. If they painted the plaster before it cured the paint fell off. maybe modern paints don't have this issue. If you are lucky you might find colored plaster and you might like that if you do. You can test a spot.

put plastic on the floors and old towels to sop up and make sure it isnt' causing damage below as some may drip down to the next floor. check for that.

once clean I'd use something like kilz primer, to create a barrier and give good adhesion. use a good oil based primer you want a good base.

You can use plaster for patching if you like. or drywall mud. the plaster will fill big holes and set. the mud can't be put on too heavily.

I have two tricks for altering the drywall mud. the taping mud has more glue in it ( binders) you can add a spoonful more white carpenters glue to a fist sized clump of mud and it'll really harden up and really stick , be careful it is very hard to sand but you can fill some holes cracks etc. I just buy a gallon jug of yellow glue and it's about 20 bucks, lasts a long time. dont; put glue in the mud you use to level and fill, only for cracks and taping, so the mud sticks better. wipe any runs off when it's still wet.

the other is to make a "pizza" Ill find a video on that technique. basicly take cold water, add plaster until it absorbs all the water, mix that with your drywall mud and now you can fill big holes and cracks..
https://www.youtube.com/watch?v=sp-RatKtLYU

plaster is harder to sand, and drywall shrinks and if you put it heavy it shrinks and cracks. the mixture in the video combines the two properties allows you to fill bigger holes and stuff.

If you want to just use plaster you can. the thing with plaster is it sets fast so you have a time limit. with drywall mud you can just add water if it gets too dry. drywall mud is easier to sand.

there is a similar product you can buy , its usually a powder and contains mud and plaster used to fill drywall gaps after you put it up, before taping. I don't like buying too many products so I use the above.

I prefer to make them flat and perfect but you don't want that so you can decide when it's flat enough to meet your liking, and then primer - paint.

if you have hairline cracks you can do a couple things. one is to take your box cutter and make a groove so your mud or plaster can penetrate then fill the gap. You can kind of make a triangular key if you want to.

another is to use drywall tape. or do both. Personally I soak the tape in carpenters glue diluted 50/50 and then it really sticks and won't separate. then I bed the tape as normal but I can press it a bit flatter as the glue helps bond it. If you just use mud like drywallers normally do, you have to leave some mud behind the tape so don't squeeze it down as much. that makes for more filling because the tape sits higher. If you use the tape you have to feather it out with mud. I did one room and it had so many cracks it was like a spiders web gone mad but years later it is fine not one bit of tape bubbled or lifted and no plaster cracks. I made mine perfectly flat and even used corner bead to clean up the corners. You could paper tape the corners if they are cracked and that might give you the look you are after. You just don't wan the cracks telegraphing through your paint later.

the way I do it , glue the tape on, flatten it right down. I use mud but I draw it flatter than the drywallers do. a drywaller will leave mud on top of his tape to create a hump that spans beside the tape , then when you do the fill coats you have that base to allow more fill to hide the tape. my technique requires extra steps because I pres it right down then work on my fill layers.

the way a drywaller does it , if he doesnt' use taping machines is to bed the tape and runs his 6" knife across the tape on 45 degree angles. then do a rough sand. the mud oozes a bit near the edge of the knife and this creates a "bridge" then on the next fill coat ( with a wider knife) the bridge carries the knife and allows more fill. It's because it is hard to build the wall up by say 1/16" evenly with a knife otherwise, the knife wants to follow the contour of the wall. with your walls, because you wan the wavy effect of the plaster you can hold your knife at a steeper incline and that will just scrape along and fill.. and follow the contours of the wavy plaster which you wish to keep. If you want it flatter then you hold the knife flatter to the wall and this deposits more. the consistency of the mud is really important and it's surprising how thin you can make it if you like filling it and making it absolutely flat like a drywaller would strive for.

my technique for filling is basically to get about a 1 inch bead along the front edge of the blade, clean the back of the blade and the knock the corners off. put the mud on the wall the length of a stroke first. usually I do this three times to get a good arms length.
then once you have the wall covered with a little layer of mud repeat but this time press more and pull back in one fell swoop. on the second stroke I take off more than I add to allow the dips to fill.. leaving it very flat behind the knife,, for you , since you dont; want it flat you will hold your knife at a steeper angle and that will follow the contour of the wall more. practice and you'll see what I mean the angle of the knife is part of the knack.

usually they use stiffer mud for filling initially and thin it as they get to the finishing coats. by the time I'm skim coating the mud is like porridge , just thick enough that I can keep it on the knife. for you you might want it stiffer but dont be afraid to add water. when I get a fresh box of mud I put it in a bucket , add water and mix it really well with a drill attachment then let it sit overnight to release the bubbles. it comes thick and lumpy but not with hardened granules.

careful how you take mud from the bucket, take the top off leave it flat, if it hardens up at all you throw the top away. If you dig holes and it hardens because you forgot the lid for a while then you can throw out the bucket.. the little hardened bits will leave lines as you apply your mud. don't use mud if it's got hard bits in it.

some use a platter some use a tray. I use a try and I do a lot of mixing, this breaks the bubbles and minxes the mud to a consistency like thick pancake batter. as you go if you want it wetter just dip your knife in a bucket of water and keep going. putting mud on and taking it off dries it out so you replenish what you use to keep the consistency even. if it gets lumps in it , throw it out, start again fresh.

a common error is trying to not build enough of the the mud over the tape then you can get a ghost of the tape. usually they use taping mud for taping and corner bead ,it has more glue in it. regular mud can be used for filling and there is finishing mud for finishing coats of mud , it is finer. I use all three but you can get by with one product.

some like the mesh tape. I hate the stuff myself.

you have other options if you have no insulation you may want to think about that before you go.. I think it's a good invention ;-)

the quick and easy , use green glue on the back of 1/4 drywall leave the wallpaper and all the issues behind, and you'll be done a lot faster but If you want the plaster look it will be too flat for your liking. adding drywall causes other issues with the difference in thickness unless you take the wall apart add insulation wiring and drywall , it isn't as authentic I agree. different situations call for different measures. once I get behind the drywall knife I want it flat and perfect and making it wavy bugs me but I can see the difference and in some houses it's part of it's heritage appeal. Your desire is to keep the plaster so don't go too nuts with the mudding. Just fill the holes and cracks that bug you.

If you don't want to use mud or tape you don't have to. and you can just use plaster if that is your preference. Maybe you get bonus points here for originality of materials ;-) your preference of course.

the flatter the sheen of your paint the more imperfections are hidden. I like mine very flat and perfect and Then I use kitchen and bathroom paint everywhere. Its a bit glossier than the flat paints that are so common. to me that bit of gloss reflects the look of the older oil based paints. I like it because it's washable. the flat paints have a lot of grain that traps dirt. going to a more glossy surface will show all your ripples more.. If you wanted it really glossy then you have to work harder on the flatness to hide the ripples. maybe you wan the ripples to show more.

I like to use low stipple rollers, thin the paint a little do more coats that gets it flatter and more perfect.. of course there are limits. I did my attic in oil base and didn't want the stipple so I rolled with one hand and backbrushed it down flat as I went to knock off the stipple.. maybe that would give you the look you are after. The paint stipple is from the splitting of the paint on the roller. It helps hide the imperfections just like flatter paint does. the old oil based paints self levelled more I think and the trend now is for more stipple and latex paints, to speed up the drywalling because it hides stuff.. You might go the opposite direction to show the waviness and ripples intentionally.. True gloss usually looks horrible to me unless it is something really flat and perfect like a car. but you can adjust the paint to your liking. I work hard to get the walls flatter so that I can use the more glossy paint without my imperfections showing.. You want the work to show a little , at least the waves that are there so you won't do so much skim coating and flattening the waves and sags. hold the knife a bit more perpendicular and it'll follow the wall and deposit less. flatter angle leaves more mud, steeper angle is more of a scraping action.

User avatar
Willa
Revered expert in almost everything
Posts: 1369
Joined: Tue Dec 06, 2016 9:46 pm

Re: Help with plaster walls, please.

Post by Willa »

Hey Manalto - in the house I owned with my ex, wallpaper and painted-over-wallpaper was in every single room, including the ceilings.

The Paper Tiger thing was pretty useless, the enzymatic wall-paper remover was useless. The only thing that made wallpaper removal somewhat easier was an industrial wallpaper steamer that we rented. The wallpaper steamer did not affect the 1870's plaster at all. There might be regional variables with regards to plaster composition. Walls with wallpaper painted over by oil paint DO benefit from a Paper Tiger type scorer, which will help the steam penetrate to the paper surface.

It was slow going as the plate with the steam is about 8 x 10". You have to stand there, hold it against the wall, scrape off the paper then move to the next section. Beware of the scalding drips, too ! You would NOT want to suffer through this process in a hot summer, either.

If there are areas where the wallpaper will not budge, shellac over this. The shellac will prevent the wallpaper from absorbing any moisture from a joint compound, etc. skim coat , which you will need to do to level out areas like this. Shellac means shellac - not polyurethane, etc.

NO LEVELING COMPOUND ON THE WALLS ! No, no, no ! You need something that will form a chemical bond with the existing plaster, and that you can sand.
Unless you are a skim coating savant, you will probably need to sand the areas that have been patched or repaired. It sounds like you like the rougher finish - where the imperfections show. Less sanding will give you this effect. The finish of your wall paint will also minimize or highlight these imperfections.

If you need to skim coat large areas, be sure to use the OIL BASED PRIMER. A water based primer can reactivate large patched or coated areas, while the oil based formula will not.

See Jane Drill has some very good how to videos, including plastering techniques. Most people want the smoothest possible finish - so the how to advice aims at that. I'm not a super skim coater, so my repairs were improvements - but my walls are not what could be described as flat, while they are now smoothER. Anyhow - have a look:http://seejanedrill.com/category/videos/finish-trades/

Here's a photo of one the bad walls in my stairwell. You can see patches of painted over wallpaper, cracks, holes, etc. plus that awful color:

36badwall.JPG
36badwall.JPG (564.7 KiB) Viewed 843 times


Here's that same area photographed when I was repainting the stairs and trim a few weeks ago:

_DSC0003.jpg
_DSC0003.jpg (1.15 MiB) Viewed 843 times


Here's looking in the opposite direction when all the painting was done. The trim is high gloss, the walls are eggshell. Even with an eggshell finish the slight imperfections are visible but to my eye, not unpleasant. All the walls in the stairwell area were in the same terrible condition as my first photo.(Also noted is the not 100% perfect match of the touch up paint, applied two years later after the recent trim painting):

_DSC0013.jpeg
_DSC0013.jpeg (1.3 MiB) Viewed 843 times

User avatar
SweetCottage
Just Arrived
Posts: 15
Joined: Tue Dec 06, 2016 7:17 pm
Location: western MA

Re: Help with plaster walls, please.

Post by SweetCottage »

My house had textured plaster walls (kind of a stamped design) but the texture was failing in various places and old fails had been patched but with no way to match that pattern. Plus many, many cracks. I have learned that, long-term, smooth is the easiest to patch seamlessly. I, and a helper, used plaster buttons, mesh tape, and sheets of fiberglass screen to patch holes, stabilize cracks of all sizes, and fully skim coat smooth. One room I skim coated with Easysand 90 but I found it a pain, still too fast, and switched to pre-mixed buckets of joint compound. That fit my working habits more easily. I completed 3 rooms downstairs, staircase, and upstairs hall in mid 2016 and have had no cracks come back.

If you need a little texture, you can add painter's sand to mud or paint for some texture. https://www.homedepot.com/p/Homax-Sand- ... /202061377

My kitchen plaster had many layers of enamel paint straight over the brown coat rough plaster. I will need to fix a few patches with the above to blend them in.

I also highly recommend a wallpaper steamer. In an old apartment the landlord said I could take down the wallpaper in the bedroom and bathroom. Bathroom with vinyl paper was easy. Bedroom, could only get one inch pieces off with the Paper Tiger. I bought this steamer (though it was $90 back in 2011) https://www.homedepot.com/p/Wagner-915- ... /202719943 and made much better progress on the wallpaper. Could not have done it otherwise.
1920s English cottage style home

User avatar
Manalto
Inventor of Knob and Tube
Posts: 2114
Joined: Tue May 16, 2017 11:09 pm

Re: Help with plaster walls, please.

Post by Manalto »

Thank you, everyone. Your feedback is greatly appreciated.

I don't prefer rough walls per se; that's what I've got and I don't object to them. Any repairs would best approximate the gritty texture of old plaster, rather than the perfect smoothness of drywall. (I did an acceptable job of skim-coating the drywall in the 1950s-addition bathroom.) I'm going to try Phil's suggestion to do horizontal scoring and maybe get a steamer if the wallpaper still resists my efforts. Ideally, I'd like to get the walls cleaned down to the plaster, which is a warm buff color. I think natural woodwork with a couple of coats of shellac would look terrific against it.

Since the weather was warm this winter during my visit, I had the house opened up for much of the time. The low winter sun poured into the house and accentuated the hideousness of the depressing poop-brown walls. (They're actually a dark plum color, but that's way too kind a label for them.) I can't help but wonder about the mental state of the person who chose to live with that color and the garish lavender trim. I'm getting impatient to see it go away.

This project is probably going to have to wait nearly a year but now, thanks to y'all, a plan is beginning to gel. It's encouraging to hear that I was misinformed about the plaster softening from the application of steam. (Why do people pretend to know about things when they don't? Because there are no consequences?) I would be a masochist if I were to take on this project or stripping woodwork with a heat gun, in Gulf-Coast Alabama in May. The weather's already hot enough by then to make those jobs inadvisable.

User avatar
Willa
Revered expert in almost everything
Posts: 1369
Joined: Tue Dec 06, 2016 9:46 pm

Re: Help with plaster walls, please.

Post by Willa »

Manalto wrote:It's encouraging to hear that I was misinformed about the plaster softening from the application of steam. (Why do people pretend to know about things when they don't? Because there are no consequences?) I would be a masochist if I were to take on this project or stripping woodwork with a heat gun, in Gulf-Coast Alabama in May. The weather's already hot enough by then to make those jobs inadvisable.


It is my understanding that a wallpaper steamer can really damage drywall walls. In my experience it did not make any of the old plaster or even the iffy repaired areas the least bit mushy.

Well, it's up to you if you want to explore the length and breadth of your suffering with with a heat gun and steamer in the hot and humid seasons. We did the stripping in Feb. of a Canadian winter, and it was a sweaty damp job, that left the windows steamed up.

I too have suffered with horrible and questionable paint colors. from the PO While it seems counter-intuitive, getting a coat of primer on the walls and trim can help you to see the room differently - even if you will need to do plaster repairs on top of that and completely repaint the room later. You can get primer tinted. The dark plum with lavender combo sounds heinous. Getting that out of your pysche may open up new ideas about how you will use that room. A couple of gallons of primer plus the effort to get that on may bring you unexpected relief.

User avatar
Manalto
Inventor of Knob and Tube
Posts: 2114
Joined: Tue May 16, 2017 11:09 pm

Re: Help with plaster walls, please.

Post by Manalto »

Willa, you and I are particularly (if not unusually) color-sensitive, which makes me wonder if my wall color and gin consumption this winter were related. Your suggestion is such a good one that it caused me to chuckle. It would be well worth the effort. That godawful color combination really got under my skin this last visit, especially the stairwell to the second floor with its vast expanse of that repugnant brown-purple.

User avatar
Willa
Revered expert in almost everything
Posts: 1369
Joined: Tue Dec 06, 2016 9:46 pm

Re: Help with plaster walls, please.

Post by Willa »

Paint is such an inexpensive solution to an unhappy house. Well, at least for a person with competent painting skills, or the patience to learn. I am at about 70% with choosing the right color, the first time, but I am unashamed to paint over my own bad choice that isn't working. Tinted primer is a good way to test a color, too.

I am just getting ready to start on the last surviving room painted BM Jackson Tan (a chocolate milk color), which is quite unhappy with the too blue charcoal trim (all the PO's choices). This room is bright with western exposure. My original intention(as of two weeks ago) was to switch my bedroom to this room. My bedroom currently overlooks the problematic gas station neighbour, so I can hear the tire compressor, doors slamming, car stereos, etc. which is worse in the summer with the window open. I like a dark bedroom. Upon further consideration I realized that it would be smarter to move the sewing room ( the smallest room on the main floor, off the dining room) to this room, and move the bedroom there. It will be cooler in the summer and quieter.

This room is very bright in the afternoon so I felt sort of guilty contemplating a very dark wall color and blackout curtains. Of course this means I now have to fix the walls and paint two rooms instead of one, but I think this is the best solution. The chocolate milk color will be replaced by something lighter, with all the trim brightened up. I know the room will feel incredibly different when it is a better/brighter color. Right now it is one of those rooms with "potential".

Both the current bedroom and the sewing room are painted a dark army green, with dark charcoal trim. These are the two smallest rooms in the house (besides the powder room). The dark walls work really well for a bedroom, less so for a sewing room with southern exposure. The PO painted all the rooms with a medium or deep base wall color which just wasn't working, and they weren't working well together, either. The turmeric yellow with that grey was really the worst. It seemed to have been used on the walls in the roughest shape - as some sort of dazzle camouflage I guess ?

Rooms that are painted the wrong or unpleasant color just feel so awful to me.

It's like being on a date with a person who is just not a good match. While they might be attractive or whatever there is just not that feeling of compatibility which can be so awkward and claustrophobic.

It's time to break up with that liver and lavender and move on !

Post Reply