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My husband is planning to use joint compound to patch our plaster walls.  I recall reading somewhere that this is not a good idea as they are not compatable or something.  Also, I hear a great deal about Master of Plaster and how it will stick to any surface.  Is this to say that other products will not adhere to paint, etc.?  Finally, I would like to skim coat the walls but have NO experience.  Is it difficult to get a smooth wall surface?

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Try a wall in a closet if you want to do it yourself.  If you can make that smooth, then great. If not, only the inside of a closet will have weird waves in it, and no one looks at such walls.  I speak from experience, because I have done some pretty shoddy work on the walls and ceilings of some of my closets.  They were untouched when I bought the house in 1995 with original horse hair plaster and original paint on the plaster, having never been wallpapered.  Lots of crumbling and water damage for me to practice on.
My last house I hired a plasterer to skim coat the walls after all the paper was removed.  Some of the workers made some bad gouges in the walls.  He rolled the walls with some kind of sticky adhesive type paint, don't remember the name. After that he skim coated the walls and ceiling with something called "Hamiltons soft top" mud.  It came in a box and was yellowish.  It was great because it was soft and didn't need sanding,he just washed it with a sponge so no dust.  Once it was primed it was as hard as plaster.  I lived there for 14 years and never a problem.  Since I left the new owners stripped the wallpaper I put up in 1 room and said it came off and they had no problems. That means 24 years with no problems, you can't beat that.
Thanks for all your input!  Still not sure what's best to fix that cracks with, but Hamilton's sounds good.
Erin, I make my living teaching and consulting about traditional building materials and craftmanship. Your walls are likely a base material of calcined gypsum or lime. Because the walls are an old school material its very hard to get modern materials like joint compound with its glue and talc to bond with the older natural material that hardened over time by an air drying and absortion of CO2. Virginia lime works specializes in making repair materials that will bond in the old cracks and also keep your walks authentic. Jeff Price is the director of sales and these folks are the go to people for period lime materials for brick, stone and plaster prior to the advent of portland cement and drywall around 1917. The other method you mentioned is similar to what I had to do to my 1940 bathroom once the wallboard was stripped. All the damaged gypsum was sealed and consolidated with Zinsser Gardz and then skim coated with a blend of Plus 3 and mildew resistant latex paint. I used the new extra thin fiberglass tape over the dynamic cracks and the rolled out the skim coat with a good roller and finally smoothed out with a 14 taping knife. Great results! The rest of my house is 1860 lime plaster that gets treated with period materials. Cracks get sealed with a very special blend that goes back thousands of years and in our modern times is referred to as DHL lime injection. US Heritage in Chicago is the supplier. If you chose to use it I can give you some tips to make it come out well. Happy plastering knowing you are working with an ageless material of the highest skill level.
Thank you.  I'll look into this.  I don't have a lot of confidence in my skill level - none.  I guess I have to start somewhere.  No comment on the Master of Plaster?  Also, I've heard Big Wally's is the way to go to re-attach loose plaster to the lath.  Any experience with this?
Hamilton's just sounds like a brand of standard drywall compound ("mud").  Mud stays water soluble forever and can be smoothed with a damp sponge at any time after it dries.  Once painted, it's nearly impossible to tell painted plaster from where it was skimmed with mud.

I have no idea what any of you are talking about... I have had absolutely NO problems whatsoever using standard drywall compound ("mud") on any of my plaster walls over the last 21 years.  Some areas over bare plaster, some over old paint... no peeling, no chipping, no flaking, nothing.  There is no reason why "mud" wouldn't stick to a clean plaster surface (it even sticks to wood).  Areas with gouges down to the base coat I've filled with "mud" and had no issues at all.


The best part about drywall compound is that it's 100% NON-destructive.  If you think you ruined something, simple water or steam will remove the mud no matter how much time has passed.  However, try making your patch with plaster without enough skill or experience... no amount of sanding, water, or steam will undo that mistake... just get out the hammer & chisel.


And finally, the compound's ability to remain water soluble makes it very easy to work with even after it dries.  A damp sponge is a dust free way to re-smooth the surface.

Thanks for commenting.  I hope you're right because my husband went ahead and used it anyway.  I guess time will tell.  I appreciate everyone's input!

I'm sure you'll be fine.


I can only see it peeling, chipping and flaking if the original surface is peeling, chipping and flaking.


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