Wet carpet and walls

[playinabout]

I have a damp wall that has been growing mould on it I have removed the mould every year for the past two years and now looking for a full fix the walls cavity wall insulated there is no salt on the wall or any other discolouration the only discolouration I have is a nail that holds the skirting board in place has made the surrounding area rusty the carpet is wet on the underside of a rubber underlay and the top part of the carpet is discolored damp I have recently had damp proof done and the plaster and the inside of the walls sorted but I'm wondering how come I'm having condensation or damp in a different area of my house in the same room where have never had it before lifted the carpet to see in the underlay was discoloured the carpet gripper turning mouldy my floor is concrete with some sort of black tile on top it's thin the house is 1955 built it has vents on the outside of the house that have been closed off at the floor level when the cavity wall insulation was put in if I get on the floor and look under the skirting board I can see straight outside into the light as there is a slight gap between my inner wall and my outer wall due to settling in the concrete slab over the years I was wondering how do you fix the settling so I no longer can see outside and is this the cause of the damp on the walls and in the carpet. I only noticed when I had an infestation of ants coming into the house and I lifted the carpet to see the gap on the outside I have been thinking of just concreting the outside slab where I can reach and repointing that little section on the outside but I have put white sealant between my skirting board and the concrete floor will this have caused some of the damp.

 

[bobasd]

why not get some photos up showing the inside damp and the outside showing ground level.
CWI is always suspect for bridging damp across the cavity so have a good look all over th nearby walls.
why did you have damp work done?
might be best bet for you to have a dead serious look at all outside wall skirtings and plaster,look for any mould or damp signs.