Greetings
First time poster on this great forum so be gentle with me and please excuse my ignorance.
Common problem: rising damp through gypsum plaster on 19th century rubble stonework here in beautiful Cornwall. Damp consultant report (who has also quoted for the work) has suggested both vertical DPC plus tanking render AND hydraulic lime plaster (and a roof fitted ventilation system to gently force old air out). At a substantial cost. Bells are ringing...
I thought it was an either/or between tanking and lime plaster, the former effectively waterproofing by diverting water away from the plaster, the latter allowing the water in but to then evaporate gently into the room where appropriate heating and ventilation takes care of it.
If a vertical DPC is installed, then the tanking (2x10mm sand/cement with waterproof additive; 2x1.5mm cementitious tanking compound) then I don't understand what function the 12mm of sand/cement/lime plaster and 3mm limelite would have as a breathable coating.
I've read a LOT of posts here and elsewhere but haven't quite found the answer (although I have seen a lot of Celebrity Grudge Matches between PCA and RICS affiliates ).
I'd appreciate any help. Have I got this wrong? Am I doing the consultant a disservice?
The Grockle
First time poster on this great forum so be gentle with me and please excuse my ignorance.
Common problem: rising damp through gypsum plaster on 19th century rubble stonework here in beautiful Cornwall. Damp consultant report (who has also quoted for the work) has suggested both vertical DPC plus tanking render AND hydraulic lime plaster (and a roof fitted ventilation system to gently force old air out). At a substantial cost. Bells are ringing...
I thought it was an either/or between tanking and lime plaster, the former effectively waterproofing by diverting water away from the plaster, the latter allowing the water in but to then evaporate gently into the room where appropriate heating and ventilation takes care of it.
If a vertical DPC is installed, then the tanking (2x10mm sand/cement with waterproof additive; 2x1.5mm cementitious tanking compound) then I don't understand what function the 12mm of sand/cement/lime plaster and 3mm limelite would have as a breathable coating.
I've read a LOT of posts here and elsewhere but haven't quite found the answer (although I have seen a lot of Celebrity Grudge Matches between PCA and RICS affiliates ).
I'd appreciate any help. Have I got this wrong? Am I doing the consultant a disservice?
The Grockle