wall sealer

[Jayluvit]

Hi all,
My mum has had a conservatory up now for about 15 years and the render was falling off on the inside.
She has had it stripped back to the brick, (single skin wall )plaster boarded and skimmed. It was also treated on the inside with some kind of bitchumen (excuse spelling) before the plaster board went on.
The external side of the conservatory walls is now the next plan to get done.
The walls were painted the same colour as the house and this paint is now peeling and bubbling in some places and I plan to repaint with masonary paint.
I was told about Thompsons Water Seal Ultra but after phoning their technical help line I was told that you can not paint over the water seal or put the water seal on top of the paint. It seems that this for just for bare brick walls.
As I will have to paint these walls so it matches the rest of the house is there a sealer that can be put on before or after this stage or does the masonary paint offer that protection?

 

[Jayluvit]

** bitumen

 

[joe-90]

Masonry paint will seal but it sounds like you have damp issues and the bubbling is the moisture making its way out.

 

[Jayluvit]

Thanks for your reply Joe 90.
Does the masonary paint offer the same type of protection as you would get with a sealer?
Its a single skimmed wall so am guessing this problem will always pop up every few years. It also gets quite condensated and there is no heating in the conservatory.
Will having the bitumen on the internal wall help with keeping the damp away?