I have done this myself and it is very labor intensive. The original wallpaper was directly applied to the plaster and there were 7 layers of finishes on top of the original paper. 2 of those layers were wallpaper and the other 5 were paint. We tried everything and finally found a great combination that worked.
1. score the layers of paint in an X-type fashion, about 12 inches or so apart to make a sort of latticework of cuts
2. mix white vinegar and water in a spray bottle
3. spray the wall to saturation
4. let the liquid set for 15-20 minutes
5. scrape with a slightly flexible putty knife with rounded corners
6. spray the plaster with the vinegar water and scrape again to remove the glue residue
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Joy Coleman AIA
Principal
TreanorHL
Kansas City MO
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Original Message:
Sent: 11-01-2018 07:52
From: Margaret Chalk
Subject: Removing Painted Wallpaper from 1940's plaster walls
Does anyone have a reasonably quick method for removing 1940s wallpaper, glued to 1940s plaster walls, which has been painted over with oil primer and 2 coats of latex? So far, scoring, glue removal spray-applied, and steaming , has made very little difference in achieving the removal.
Margaret K. Chalk, AIA, NCARB
Principal Architect
MK CHALK ARCHITECTURE, PA
PO BOX 622
MOREHEAD CITY, NC 28557
(252) 726-3099
mkcarchitect@ec.rr.com