sand and cement or bonding base coat onto bare brick?

[cezeta]

after stripping 1920s blown lime plaster im now ready to have the walls re finished.

two plasterers have given advice, one saying sand and cement base followed by a top skim of plaster the other saying that gypsum bonding followed by a top coat of plaster.

so which is best?

 

[roughcaster]

If you plaster straight onto old brickwork/stonework, with any of the Gypsum plasters,( bonding, browning etc), you run the "high risk" of problems, with hygroscopic salts etc coming through that type of plaster, and ruining the finished wall surface. They are notorious for it, and you wont know if you're affected until after you've plastered the walls..... You can see what could happen, if you go into the BUILDING FORUM,,, date to look for,,, Sunday November 16th,,, Topic Title: "Fresh Plaster Showing Damp,Chimney Breast with photo's". You will get all the info you need there...... Cement Render,,,, or at least Scratch coat with waterproofer in the mix first,,, then plaster!!!

Roughcaster.

 

[The-brickie]

Similar to what I said on LCGB mate