blown plaster

[marsaday]

I am hanging a new rad in the lounge and the plaster under the window has blown (hidden behind a now removed storage heater).

I have taken a away the plaster and it is about 1m wide by 1m high. The stone wall is fully exposed and i have raked out the plaster between the stones as well (could be old mortar).

Do i repoint between these stones and then add the browning or do i just slap in the browning ?

 

[1john]

Greatly depends, you may well have lime plaster in which case if there is any moisture in or coming up the wall the browning will go pear shaped. On old stone houses the plaster is lime and it breathes letting the moisture evaporate

 

[marsaday]

There shouldnt be any moisture coming up the wall as this is on the first floor so any moisture will be much lower down.

 

[Richard C]

It doesn’t matter if its ground or 1st floor; if it’s an old stone wall property with solid walls moisture will permeate through from outside, that’s why they used lime plaster which also allows the wall to “breath”. If you cover such a wall with Browning plaster without any damp proofing, it will fail off in a very short time; nobody really uses that stuff now anyway.

 

[marsaday]

ok, so what is the product do i need to buy ?

Could i use a sand / lime mix. i have a load of lime left over you see. i would like to use this up if possible.

Do you also apply a finish coat of plaster ?