My plaster walls are delaminating. The 1/8″ finsh coat is coming off leaving just the brown coat. These are areas about 2 or 3 sq feet. What do I repair it with and where will I find it? All I can find is joint compound and patching plaster.
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There are washers (seen them used on ceilings) that when screwed into the old lath, or preferably studs) will hold the layers together. Then you are supposed to mud over them and feather it. I bought the washers for a ceiling, but haven't used them yet. Am thinking it may be just as easy to take the old plaster off and use drywall. I got them from Charles Street Supply Co. in Boston.
How old is the plaster?
Is this a job that is worth sinking some time and money into, or do you need a cosmetic quick-fix?
How extensive is the failure?
What room is this in?
DRC
The plaster is about 100 years old. The room is proabley 10X10 wth 8' ceilings there are maybe 5 areas 2' - 3' square that need repair. Its on the 3rd floor, converted atic so not seen very often so I look at it as a good oportunity to learn some platering, It's old enough so I hve something decent to start with and small enough so I wont be overwelmed and it is out of the way enough so that if it is less than perfect it won't matter too mcuh,well except to me ego (-8.
Ever heard of this Master Of Plaster stuff? supposed to be a plaster premix, has some lime content and can be troweled on but $40 gal sound like a lot.
jw
Indeed, a perfect opportunity to learn.
Scrape off any of the loose stuff. If you have any doubt about the new bond (I would), you can apply Gypsum Bond. Probably many products on the shelf similar, it's a bonding agent specifically for plaster.
That premix sounds horribly expensive. All you need is a bag of finishing plaster, a mixing paddle for an electric drill motor, a bucket, a trowel, a good sense of humor, and a little patience.
Use cool, clean water, and clean everything (bucket, tools, mixing paddle) thoroughly between batches. A little known fact of gypsum plaster that has put off more than one beginner is that a trace of the previous batch will set off the next batch right away.
So there you are on the second batch, everything is going as well as the first batch for a few minutes, and suddenly you have a lumpy, hot, useless mess of plaster. Throw it out, try it again, same result. Get disgusted and quit. All for a little clean-up. Don't let this happen to you. <G>
DRC
Thanks for the info, I also have a lot of plaster repair to do. As you probably know, plasterers are becoming extinct in a lotta places, but I'd rather repair it than sheetrock everywhere.
Take baby steps first.
My recommendation is to fist prime the walls - not just the areas needed to be repaired. then patch the craters with joint compound and then skim the whole wall. Sand and oil prime again prior to painting.
This will introduce you to the fundementals of skimming a wall/ ceiling. Platser is different but very unforgiving. With compound, you'll be able to go through the motions, figure your ladder/ scaffold placement/ movement and learn if you are a right to left or left to right person.
Lerarn to use a trowel with compound rather than a 10" or 12" knife. That's what you will use with the plaster. The pool trowels are the best because they have better flex and don't leave as many corner carvings, IMO.
F.
Does this room have any closets? If so, look in there for more problem areas, and do them first. That way your learning curve runs from the least visible areas to the most.
-- J.S.
Good idea, thanks. I phoned US Gypsum and they recomended thier Diamond product which has a gypsum bond agent and they gave me the name of a local supplier that is open Saturday monrings so I might be able to get some.
As long as you have some deep peeling areas (1/4" or more), I'd recommend you try filling them with Structo-Lite plaster first (I think it's a USG product but not sure). It is fairly easy to work with compared to Diamond... the Structo will stay workable a lot longer and give you a chance to practice with the trowel. You can then put a coat of Diamond over the Structo if you want to (you won't have a perfectly tight surface with Structo). Diamond is harder to work, at least for me. The good plasterers I have watched trowel it until it's getting hard, then at the end use a spray bottle to mist water onto the surface and continue troweling to get it really tight. They make it look easy and it's not. It's possible to get a glass-smooth surface with it.
You need to buy a trowel and a hawk to work plaster, IMO
Ask about the retarder for Diamond, it sets fast and is hard to use solo. Clean your mixing tools very well as remnants of plaster will cause early setting. When you get the Diamond right it's truly a beautiful finish, bulletproof too. I've used white vinegar as a retarder and thought the hardness of the finish was compromised.
Starting with a closet is a great idea, Diamond does not sand well.
Durabond would also be a consideration, maybe paired with the 3 foot wide fiberglass mesh. Throw some plaster washers in there as needed, but predrill you holes - lath is too dry to power the screws in.
There's also a plaster called "EasySand 90" and "EasySand 60" The number is the time in minutes it's supposed to be workable. And of course, it's supposed to be easier to sand than regular plasters. It's recommended for beginners.
-- J.S.
Here's a place to look for plastering information:
http://www.ornamentalplaster.com
-- J.S.
I'm about 3/4 done with a kitchen remodel that had plaster, and then drywall on the new walls. Following advice fron Frankie, Firebird and Piffin I sanded, washed, primed and used durabond. Turned out great! Check threads from about a month ago on a bathroom remodel involving wallpaper and plaster.
Good Luck
MES
Thanks, What is durabond?
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SHEETROCK¯ Setting-Type Joint Compound—DURABOND¯
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A general-purpose chemically hardening (setting-type) compound that permits quick finishing and decoration.
For finishing wall and ceiling joints; ideal for heavy fills and for patching. An easy-working compound recommended for use where the strength of TUF-SET Compounds is not required.
Meets or exceeds ASTM C475.
Available in 20, 45, 90, 210, and 300 minute set times; 25 lb. bag.
See publication J17A for additional information.
Also take a look at the room and try to determine why the failure? No insulation, heated room, moisture ect and the failure will continue. Or was the room abused at some time by the homless with baseball bats?
Plaster washers are actually stocked at HD.
JWNYC,
I've been doing lots of plaster repairs, and I'd have similar recommendations as others here. For damage only to the finish coat, I typically use USG Diamond Finish plaster and/or Durabond. Diamond is easy to work with, and if applied carefully by a novice, can come out looking pretty good. Durabond is an excellent alternative... In either case, wet the brown coat and apply them, carefully. They can both be sanded, but not easily (use 60/80 grit). For Durabond, it's best to let it set up and knock down any ridges (from the drywall knife) with a drywall knife before the compound completely hardens. It cuts down on the sanding mess. If you're using Durabond 45, you should do this about an hour after you've started applying the compound. As a final coat, skim with an easier to sand joint compound, like USG Easy Sand (if you like setting compound), or bucket pre-mix. Then you can get your ceiling looking really good...
One poster mentioned using a plaster bonder on the brown coat prior to the finish coat. Be careful, as some finish plasters advise not to do this (I believe Diamond is one that recommends NOT using a bonding agent). The bonder can actually hinder the bond for some finish plasters. Bonders are typically used in cases such as plastering to concrete/brick, or if you have blue-board that has been exposed to UV-light for too long (in which case the blue becomes not-so-blue board, and the plaster bond is lessened).
In any event, check for sources of water... that's where 90% of my repairs come from. Roof leaks, leaky plumbing, the animals that weren't let out for months, etc. The scratch/brown coats didn't usually get damaged, but the finish coat delaminated. Also, temperature extremes can cause the same thing (if the plaster freezes, your finish coat usually lets you know.)
Also, for damage to the scratch/brown coats... I'll either use Durabond and mesh tape/screen if the repairs are small, or use Durabond Red Top wood-fibered plaster. I use that since it's come highly recommended, and has worked well for me. You can either mix it with water straight out of the bag, or add sand into the mix. In any event, I follow the manufacturer's instructions...
I have some pictures of the work in progress. This is the room after stripping the wallpaper. Sorry I can't figure out how to imbed these in the message. Having AC inthe room makes it a much easier job.
http://geocities.com/jw_nyc/P1.JPG
http://geocities.com/jw_nyc/P2.JPG
http://geocities.com/jw_nyc/P3.JPG
The pages are not available. Check it out.
F.
I don't see the pictures but if the finished coat is only 1/8" your best bet is the duradond 45-60-or 90. if you work with this stuff before.
If not, you can use regular joint compound .
Just for info the best way is to mix the joint compount with plaster of paris and a small amound of cheap latex primer. About 20/1/1. On small doses. If you learn this system you can repair any plaster damage walls EZ-FAST-with no mess or sanding.
In any case like others mention before..Remove the dust of the brown coat with a small broom or brush.and wet the brown coat 2-3 times with a spray battle And where the new plaster meets the old finised coat you have to force the new behing the old to create a key.
I think your best bet is the premix joint compound.
.
Sorry I have no idea why these don't come up. If i cut and paist the link into my browser it works if I click on the link it does not.
http://geocities.com/jw_nyc/P1.JPG
http://geocities.com/jw_nyc/P2.JPG
http://geocities.com/jw_nyc/P3.JPG
Thanks for the advice
JW,
The advise here has been good. Learning how to work setting plaster is a great skill, and the resulting product is better than drywall/spackling compound once you get the hang of it.
Working setting plaster is a lot like working cement. You will want to have a hawk and a plaster trowel, which is a lot like a rectangular cement trowel, but a bit shorter and wider. Slightly rounded corners are helpful. It is also useful to have a good drill and a plaster or paint mixer to mix the plaster, doing it by hand with a paddle is not very practical. You mix your plaster to about the consistency of stiff mashed pototoes, don't mix more than you can apply in about 15 minutes. Dump it out of the bucket onto a moist scrap of plywood. Have your helper clean the bucket.
As the others have said, wet the surface before starting. After spreading the plaster and getting it as smooth and level as possible, you let it set until it is getting harder to leave fingerprints in it. Then you wet the survace with a sprayer or use a paint brush to splatter water on it, and trowel and trowel. Like finishing a concrete floor, you will be working a slurry off the surface, especially from the higher areas, and working it into the lower areas and voids left when you spread the plaster initially. Spray and trowel and feather. You will get to a point when the plaster is too hard to feather, hopfully when the surface is glass smooth and you have done the entire surface. It takes experience to know how large an area to work on so that you can finish it before the plaster sets completely. I watched plasterers work right into corners without using a corner trowel and leave a smooth corner along both planes and found I could do it myself, the plaster sets and you can work the smooth surface into the corner without gouging the other side, unlike compound.
The nicest part of this is that when you are done, you are done. No going back for the next several days to apply another layer of compound. Very nice.
If you are really having trouble feathering into the existing plaster so that you can't see the interface, you can cheat afterwards with some joint compound. I've found that I can spread compound on plaster, but often plaster on compound flakes off. Probably something to do with coefficient of expansion differences.
It takes practice and you will drop a lot of plaster on the floor. Make sure your tools are clean.
thanks for the advice. I especialy like the part about giving the bucket to my helper to clean (-8
As to buckets, is plastic ok or do I need tin or something else? I suspect that if I start my cleanup early enough plastic is ok.
interesting your comment about plster over joint compound as other have mentioned using it to fill lower levels before plastering.
The instrucions onthe bag of Diamond ( yea I read them fromtime to time) say nominal thickness of 1/16" and some of my repairs are thicker so I was thinking of using joint compound to fill lower areas, sheetrock all-purpose ready mix? Someone else sugested Easy Sand 90 which is sort of what I'm limited to at HD since "real" store aren't open onthe week end when I can get to them.
jw
Old drywall buckets are fine, thats what I see plasterers use and what I use, you tend to have a lot of them after a while.
I'm afraid I don't recall what finish plaster I used, I am thinking it was a gold bond product, but I would have to dig out my last bag.
Hopefully those here more familiar with the Diamond, Easysand and other products can advise you about practical thickness.
IF you have already put down some compound, I would go ahead and go over it, I had some spalling of thin finish plaster over compound, but the pros I had in at the start of the project feathered their finish plaster over compound and it is still in place.
If you need to fill, get a bag of scratch coat and start with that, but it looks like the coats you need are pretty thin, 1/2" or less? If they are deep, it may be that you could put down a first coat of what you have as filler and the next day apply the finish coat. If your coat is too thick, it will crack as it sets, so leave the thick fill coats just shallow of the finish level.
I would err on the shallow side, you really don't want to have to sand this stuff down like you can compound.
Great thank, now all I need is the helper to clean my buckets. Guess I should have had kids.
Hello plaster-ers,
This is an interesting thread for me as my plaster walls are in need of repair. I have used StaySmooth Lite 45 on drywall because that's what HD has. I have had pretty good results mixing up small amounts in a mud pan with a margin trowel. My questions are these: Is this compound suitable for plaster repair, or do I need to go to drywall supply house to get the products you mentioned? How should I prepare the walls that have old flaking paint? Some of the paint has flaked off of the original plaster, in other areas the more modern latex paint has separated from the original paint. The paint is often alligatored.
Thanks...
okay, the stupid question; why is plaster so much better than joint compound for smaller patches? I had always used mud for repairs when I worked for a living, now that I am repairing my own place I'd like to use plaster but I have to convince myself that the added time is worth it, particlurarly for the small dents/dings that I have to repair. Is it really that much harder/smoother?
Ok. I just saw the pictures. What you need here is the Dinoplaster. Here how it works. I made very good money using this system.And got many referrals.
1.scrape the walls and open all cracks with a utility knife or a small stiff scraper 2.Prime all walls with Alcohol base primer.(open windows and have a fan)
And the most important item when you use white shellac is a respirator.
Then you mix the lightweight joint compound with vinyl latex primer and apply your plaster with a stucco roller. Do small sections. 1/2 wall at the time.
Then go back with a 9"tape knife and smooth the wall out. No skill no sanding no problem. Use 1/2 gallon primer to 1 -5 gallon bucket.
At the end if you have some rough spots use a wet sponge or more of this Dinostuff. And to all of you guys.You learn this technic you can make as much as $ 5.000 a day. with a crew of 3-4. you cant believe how fast you can finish a whole house. (3-5 days) And is guarantee.(dinoproof.)
Where's the pictures? When I click on the posted links, I get a Yahoo page telling me they aren't there.
If you cut and paste or copu and paste? you will see the pictures.
I don't think that Yahoo allows direct linking of pictures to an other website.
Right click on the link and copy link.
Then open a new browser window and past in that link. Then youwill get the picture.
Ah! is that what it is, a Yahoo! thing?
jw
I would also use compound for small repairs. There is a definate setup and knockdown factor, if you are doing a lot, and know how to use it, it makes sense since there is no shrinkage and one coat does the trick. You definately don't want to have to sand this though, it is a very hard surface and withstands dings and dents better. If you are patching a lot of old plaster walls, it may be worth your time to try it out.
I needed to hire and watch some professional plasterers (friends) to really appreciate the nuances. The analogy to finishing concrete is a good one, if you've watched someone trowel a slab smooth you have the same idea.
Further than that I would have to defer to the others here that have done it more than I and used some of the other products. I've never used the EasySand products, so don't know how hard it is compared to compound. I had quite a bit of horse-hair plaster walls to repair, so by the time I was done, I was getting very good at it and really appreciated the hardness of the surface and that I could apply the finish coat in one session.
This room looks perfect as-is for a teenage boy, if you have one. Just lock him in there until the testosterone poisoning wears off -- he can't do much additional damage.