Q I moved into a mid-terraced 1903 property in September last year. I had a homebuyer's survey which picked up no problems with the damp course or any damp in the house. I have since removed all the wallpaper behind the front door (an internal party wall) as it was peeling and have discovered a mass of tide marks (though no salts) and some black mould growing. The wall also feels wet to the touch and the height of the tidemarks varies between a couple of inches and about two and a half feet, there is a concrete, I believe original, floor in this area. My neighbours who share the affected wall had a damp course injected about three years ago and have had no problems since then, my own property had the walls injected in 1987 and are guaranteed for a further 10 years, however the guarantee was not put into my name by the solicitor (an issue I shall raise with them). I only noticed the problem in around November and I am aware of the problems with condensation, and have taken steps to reduce this, could this be the problem or is it more likely to be another cause? Also what would you suggest to be the way ahead with dealing with this problem, - another round of injecting from my side, or an alternative? Also how can I stop the black mould growing back after I have cleaned it up? I appreciate that preventing the damp would prevent the mould but I do have a small patch on one of my own internal walls and don't see where any water ingress is coming from.
A Mould will only grow from a pure water source i.e. rain water, tap water or condensation. It will not normally grow on a damp surface where the water is derived from the ground as this contains salts and minerals which act as a mouldicide. You should certainly get back the surveyor responsible for the home buyers report, ask his opinion and ask why he did not pick it up last September. It may be condensation and was not there then or it may be getting in around the front door frame now and was not last September. The wall has had two chemical damp courses injected so it is unlikely to need a third.
The fact that your name is not on the damp guarantee should not be an issue but the guarantee may state that assignment is necessary in a set period. It is the property that is guaranteed not the person. If for some strange reason this is an issue then most certainly take it up with your solicitor as due to a possible error on their part they could perhaps be held responsible for the cost of rectifying any damp problems that would otherwise have been covered by the guarantee that they did not arrange to assign it at the time of your purchase. If necessary ask them to write to the damp company.