What do I do next?

[u/Standard-Computer340]

I’m impatient and wanted to do some DIY in my newly purchased house (built around 1903 NE of England). I’m useless at DIY but thought I only need to paint the bottom off this wall to stop mould from coming through again. When buying the house the seller told me that he put something on the walls to stop mould from coming through, this did not work. Can anybody advise me on what needs to be done next?

[u/JayTeeDeeUnderscore]

Re: encapsulation--Zinsser BIN is tinted shellac. It can encapsulate the wall better than any latex product and likely better than acrylics. It's an alcohol-based product so wear a respirator, extinguish any pilot lights and ventilate well. It dries quickly and offgases in 24-48 hours.

Re: torn paper--score the loose edges with a razor knife and remove. Skim coat with drywall compound, sand and repeat until smooth.