# Setting compound preparation on old painted plaster



## McCovey (Sep 18, 2017)

Overview: 1920's old apartment building converted to condominiums in Oak Park, Illinois. Brick walls between adjacent units, covered with plaster without lath. Multiple years of paint, some may be lead-based. Only one wall in master bedroom has that type of wall. Started to install large crown molding. Three walls had previously been resurfaced with drywall over plaster lath, thus are uniformly smooth. 4th wall is extremely irregular wall surface of the brick with plaster. One particular irregular area is about 6 feet long horizontally with a gradual concave surface that has a maximum of 3/4" depression in the middle of that span, with suspicion that the plaster in that area had come off the face of the brick.

Steps taken: contacted US Gypsum technical support. Technician started to say the wall had to be totally rebuilt (but that is not an option the client would agree to); then suggested removing the plaster down to the brick however lead paint could be found. Technician very concerned with delamination of setting compound. Technician recommended potentially trying to find a wall primer that could allow using a setting compound to gradually build up the depression through multiple coats, and then use a top skim coat. He did not know of a specific manufacturer product.

Needed: Solution to resolve the irregular wall surface. Is it a primer, or self-adhesive joint tape, then applying setting compound in layers with a top skim coat.


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## MrWillys (Mar 10, 2014)

Why not laminate 3/8 drywall over entire surface and finish it normally?


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## thefinisher (Sep 2, 2011)

I would mix up some brown bag durabond and then add a ton of glue to it. Then put big blobs all over wall and laminate new drywall over it. Should help level any spots and hold really well.


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## Mr.Brightstar (Dec 2, 2011)

Plaster weld and structo-lite heavy Areas , after loose cement plaster is removed. 1 coat Durabond, 1 coat topping entire wall. Smooth seamless museum quality. 


Sent from my iPhone using Tapatalk


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## McCovey (Sep 18, 2017)

Thank you Mr. Brightstar; I will use your suggestion. The condo unit has unique designed baseboards that would be extremely hard to remove and impossible to replace if damaged, some of which are slightly embedded in that brick wall plaster, thus applying a 3/8" drywall over the top is not a good option. The concave depressions are most noticeable near the top of the 9'-6" wall where the crown molding will be installed.


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## endo_alley_revisited (Aug 9, 2016)

Remove all of the loose material you can. Try using Drawtite or Guardz to hold what is left together. Then a bed of setting joint compound and Fiba Fuse or EIFS matting imbedded into the mud. Then smooth out or decorate as desired.


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## flooringguy (Mar 18, 2020)

endo_alley_revisited said:


> Remove all of the loose material you can. Try using Drawtite or Guardz to hold what is left together. Then a bed of setting joint compound and Fiba Fuse or EIFS matting imbedded into the mud. Then smooth out or decorate as desired.


Good plan


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## Alan Hoyt (Mar 26, 2021)

If lead-based paint was banned in 1978, then why should builders renew lead certificates every 5 years? Researches have shown that lead contains paints of various, including well-known, manufacturers. So only in 5 out of 21 prototypes the level of lead did not exceed the maximum recommended indicator of 0.009%. A new law has been passed for builders and repairman in New York, the EPA requires the RRP Lead Renovator Initial Course is mandatory and must be passed by the end of the year.


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