I’m hoping you experienced pros will comment and offer advice on my plaster wall repair project.
Have moved into a 170-year-old farm house with plaster walls. After removing wallpaper, have found that 10% of walls are pristine, like glass (wow, what skill they had), 10% are rough and cracked, and 80% is covered with some kind of rough gray skim coat that has pulled off in many places. There were some deep holes along window trim were I observed that the walls are brick, covered with horse-hair mortar, then the plaster. Didn’t see any lathe. Keep in mind I am a DIY, learning as I go along, can’t afford to pay someone. My wife and I recently moved to this farm where we are slowing restoring both house and grounds.
I successfully filled the deep voids along window trim, building up with a base of either pre-mixed mortar (shot some Great Stuff way back in there in spots) or Durabond. Mortar was too hard to work with, so continued with Durabond, to just below surface. Then have tried a number of compounds to skim the surface. Easy Sand seems OK, but is not convenient to mix or clean mixing bucket. Pre-mixed topping compound is OK, but USG says it does not have adhesion of other stuff. Then went to Plus 3, which I have been using recently. It seems to spread reasonably well, but my technique has been slow and awkward. I first tried spreading a very thin coat, but found it too difficult–just too patchy, and roughness still showed through. Then I went to a thicker application with a 12″ knife from a hawk (tried a trowel without much luck) using longer strokes. My thickness with the Plus 3 varies from 1/8″ to quite thin. Then there is the sanding–way too much of it. I use a 9″ foam rubber sanding block while I hold a vacuum hose with the other hand, trying to catch some of the dust that rains downs. Sometimes it think I am sanding off more than I leave. I have tried the sanding screens hooked to the vacuum, but they leave gouges and lines. The wall is quite smooth where I sand, BUT, it’s also incredibly soft. I could sand that Plus 3 with my hand. One of my questions is whether it will be firmer after priming and painting. I have taped some of the cracks with mesh tape before coating.
As you can imagine, my rookie efforts have gone incredibly slow. I’ve been working on one room for weeks, and I’m looking for ideas to help in my task. I’ve been reading about Dino mix (D-mix)–do you think I should experiment with it? I like the idea of spreading it with a roller. Remember, I’m not experienced with smooth troweling. Am I going to be sorry I used Plus 3, given that it is so soft? Should I go back to the effort of mixing Easy Sand? Durabond just seems too hard for me for a top coat. On a segment of “Ask This Old House”, they mixed water into some joint compound from a bucket and spread it with a wide knife…..would you use this technique?
Again, thank you for any ideas, advice, encouragement.
Marc
Replies
I havn't yet tried the D-mix but I have done a lot of what you are doing and I would go with the durabond. I prefer to use the setting type (45"). They have an easy sand version which I think is a good compromise betweent the hardness of a true plaster and the softness of joint compound. There is no getting around the cleanup with the hot mud.
The setting types of mud will be much better for hardness. There are also actual plaster patching compounds out there. I use one from Zinsser, but I wouldn't recommend it for repairs larger than a crack or hole, say 4 or 5 inches across. A search of the Breaktime archives will turn up several suggestions.
Use Duro bond 120 (lots of working time) to get the walls flat, then skim with EZ sand 90. Mix the mud and dump it out onto a piece of wet plywood, grab a brush , and clean your mixing bucket . I use a wooden paddle to scoop out the mud as a scratched bucket is harder to clean.
When you skim, a spray bottle of H2O will help get things smooth and slick,- keep both sides of your knife clean.
The awful thing is that beauty is mysterious as well as terrible. God and the devil are fighting there, and the battlefield is the heart of man.
- Fyodor Dostoyevski
Fortunately the plaster is secure, so no need for the washers. But sounds like people are telling me to go with the setting type compound--EZ Sand and Durabond. Good tip on using D-120 and clean up the bucket before spreading!
Marc
Edited 5/23/2005 2:21 pm ET by Marc
Marc,
Just remember that the dura bond gets hard as a ROCK, so don't mix too much 'til you have the full circle experience. You will toughen the Plus 3 surface some by painting. Don't feel bad about the time - fixing plaster like you described is a LOT OF WORK for anybody. It sounds like you are really doing a nice careful job too, so you're getting your degree at the same time.One trick we use sometimes is "thinning" a small piece of drywall, say to 1/4 for a plaster chunk "fall out" fill by sawing it thin while flat on a piece of plywood with the drywall saw or splitting it with the "5 in one", then butter the back with drywall mud and push it flush. It's faster than drying some of those fills. Sometimes we hold it at the right level temporarily with screws in the lath in the crack. By the way, it is often smart to pre drill wood lath.By the way, if you have to you can make those "plaster washers" mentioned by snipping off a square of perforated "hanger iron" (on a roll), cut a washer around one of the larger holes, set it on a board and hit it with a ball peen to "dish" it. Sorry to make such a long story out of it but you know how instructions are.
There are a couple of ways I've approached this sort of problem. I've had success with a product called Structolite. Structolite is great as a scratch and a brown coat... then follow that up with White Kote, which would be a thin finish plaster no thicker than 1/8. White Kote can be troweled to glass smooth but it has a fine aggregate in it, so you've got to be careful to screed it to surrounding areas and then carefully sponge that clean. In other words, it won't feather. For a seamless patch, I've had to touch up with a little spackle. The beauty of both Structolite and White Kote is they give you time. Structolite has a big two hour or so window before it goes off. White Kote has an initial set in about 20 minutes but it can be loosened up by re-mixing and adding just a bit of water... it remains workable for quite some time after that. Neither Structolite or White Kote is designed to be sanded but as you gain skill with real plaster you'll realize sanding doesn't play that big a role in a successful patch. If you're patching a reasonably small area, there is a product called One Kote. As its name implies, there is no scratch or brown coat... just one coat that can be be trowelled to a glass smooth finish -- but you have to be fast. Like twenty minute fast or you're in for a world of hurt. One Kote can be feathered with a trowel but it can't be sanded. No plaster will adhere well to a surrounding surface that has been painted. For skimming and/or overlapping painted surfaces, I've tried Smooth Set... they come in varieties of how fast they'll go off... you've got to keep these coats very thin, though, or they never dry right. Smooth Set can be sanded but it's not so easy. And, in my opinion, Smooth Set tends to be brittle and it cracks easily later on. If you're skimming, I'd use drywall compound or even topping mix -- I've always thought these would adhere to painted surfaces but since you have some doubts about that you may need to do a bit more research to be certain. Best of luck!
Yersmay, Fonzie, thanks for youy comments. One reason I have not experimented with Structolite, despite hearing about it, is that I haven't found it available in the area (west central OH). It sounds interesting. Perhaps if I find some I will try it on the next room.
I think I need to spend more time with Durabond and Easy Sand, learning how to smooth them--maybe try a window squeegee as someone suggested. I may even tray a little patch of Dino-mix. I think I can get a small amount of Plaster of Paris at the local hardware store. One thing I am learning is that I must try to keep sanding to a minimum. I'm so discouraged about sanding that late last night I was checking out those drywall sanding machines. I don't know if they're worth the setup time and $450. Maybe.....
Thanks again to all of you,
Marc
The easy sand is night and day for sanding over durabond; as rec'd by earleir discussions here (do a search), I do three coats for repairs; first durabound, 2nd 2 easy sand; I try to make it so I never have to sand the durabound, only knock off the ridges with the knife.
There is a big advantage to finishing plaster repairs with a flat paint if at all possible; not even eggshell, flat.
The flat won't show the imperefections, so it doesn't have to be smooth as glass. Don't worry if the primer shows some wavy-ness in your patch, the flat finish will hide it.
Edited 5/24/2005 3:40 pm ET by RickD
One thing that no one has mentioned (at least I don't think they have) is bonding agent. It helps adhere plaster compounds to paint. I imagine that whatever product you are using has a bonding agent associated with it, if you ask the supplier or manufacturer. And you should generally spray the area you are patching with a little water to keep it from sucking the moisture out of whatever you are patching with.In general, plaster is not meant to be sanded. You're supposed to trowel to a finish surface. For some products, spraying a little water on just before the final skim might help. (Not that I can achieve this either, but that is the gold standard).
I've done a ton of plaster repair, but don't enjoy a minute of it. I typically run from people asking me to do it. I agree with most of the tips here. My $.02 worth...
Durabond, excellent way to go, just don't go too thick with it. Sanding is not easy (get out your 60-80 grit paper!). For building out deep cracks, spray with water, apply the Durabond, put in some fiberglass mesh tape, and build out to just below the finished surface. Sometimes this takes two or three steps. Once the durabond has set (for each application), I usually use a wet rag to wipe down the excess on the outsides of the crack, so I don't get it building up on the finished surface. Finish coat with Easy-Sand.
Some other hints... when skimming, I usually treat the existing paint to a coat of oil-based primer first. I've had issues with latex peeling if the skim coat is a little thick. I had a whole room with peeling paint one time due to the skim coating. I was extremely unhappy, which prompted me to do the "sealing" with oil-based primer.
Wetting down plaster cracks before treating with Durabond is the way to go. Otherwise, the old plaster will suck out the moisture and weaken the Durabond.
I use bonding agents (i.e. Larsen's PlasterWeld) only on occassion. This is typically when I have to use gypsum lath for more major repairs. I tend to use it just as additional insurance, instead of just relying on the plaster adhering to the blue board. For skimming, again, I prime first, so I haven't run into a problem with either Easy-sand or Durabond adhering to the oil-based primer.
Also, for the major repairs (where I need to replace lath, etc), I use USG Red Top Wood Fiber plaster, and Diamond finish coat. Sometimes these are tough to find, and I'll guarantee "Dumpster" and "Blowes" don't carry either. Again, this is for old house repair (like my house, which has 3/8 - 5/8" plaster on 3/8" gypsum lath. Makes teenagers think twice about punching the wall). New plaster work is typically just skimmed Diamond (built up about an 1/8") on blueboard.
marc.. i'd pull up the D-mix thread, read , take notes, and go to town..
if you do one wall with it.. i don't think you'll be disappointedMike Smith Rhode Island : Design / Build / Repair / Restore
Plaster is one of the few things I'll hire a pro to do -- except maybe for behind the water heater. It's a difficult skill to learn.
You might consider doing scratch and brown yourself, checking with a screed to get the depth right, then pay an expert to make the final surface. To me, watching a good plasterer work is like watching a magician.
-- J.S.
Oh come now... it's a blast. Anyone can do it. I mean, I watch all those home shows, and I've realized anyone can do anything home improvement related. ;-)
No, you're right. I've kinda taught myself plastering, but it's taken a lot of time, and I'm still nowhere near the skill level of the pros. They do make it look easy. It's an art, having the feel of how to apply it, and knowing when to work it based upon temp/humidity, etc. Just knowing what materials work best for what situations is important.
Similarly, I tried to teach a friend how to tape and mud drywall joints last summer... best free amusement I coulda had. He nearly busted up his Dewalt cordless drill with how hard he threw it when the taping wasn't going his way. I had to explain to him it's a feel that you have to acquire.
In any event, I'll stick to repairing cracks instead of doing whole house plastering.
Try http://www.plasterzone.com/ It has plaster "kits" for patching and skimming and but it also has several videos which could help with some technique secrets. The videos are pretty darn pricey though.eric
Use the D-Mix and get done with it.
Mama mia!!!!
Marc,
I have nothing to add, but I share the same problems. I'll be trying what's recommended here.
You might want to search the archives for other Plaster Wall discussions.