What's on my wall?

[00ActionMan]

Property was built 1904 with a cavity wall. Whilst removing wall paper from internal wall there is a green sticky when wet substance covering the wall; is it a sealer? mould retention sealer? is it safe to remove, fumes etc. Anyone know what it is? I believe it was put on during construction to seal the lime mortar?

 

[noseall]

http://www.diyfixit.co.uk/painting/distemper.html

 

[ajrobb]

Property was built 1904 with a cavity wall. Whilst removing wall paper from internal wall there is a green sticky when wet substance covering the wall; is it a sealer?

no

mould retention sealer?

no

is it safe to remove, fumes etc.

yes

Anyone know what it is?

distemper was put on lime plaster to allow it to dry and to absorb carbon dioxide from the air in order to harden.

I believe it was put on during construction to seal the lime mortar?

not to seal - as a temporary decoration, much as contract emulsion is used today.

 

[Nige F]

Wouldn`t it do all that chemical stuff without the distemper My M8 left his house for 10 years with pink walls and grey ceilings - un painted plaster

 

[ajrobb]

Wouldn't it do all that chemical stuff without the distemper

Of course it would. It was just a temporary porous decoration that was supposed to be washed off after a year before the final decoration with eggshell paint or wallpaper.

"It is usually produced from powdered chalk (calcium carbonate) and size (gelatin) such as rabbit skin glue.... This material was often specified to provide a temporary decorative scheme on new lime plaster which is still carbonating, because of its vapour permeability. However, it is inappropriate for walls which have continual damp problems, as eventually the glue binder will become depleted."