Laminate flooring on old concrete floor

[dy]

Hi, I'm new to the forum.

Have been decorating my newly bought ex council house which has a concrete floor in the living room with an outside wall. It used to have carpet but got rid of that and put laminate flooring on with beading along the skirting. Although the outside wall has damp which we're in the process of treating, I didn't notice any damp on the interior walls. I don't know if it's a coincidence or the fact that the laminate flooring was put in but we now have what looks to be damp on the interior walls. There's no smell but discoloration (cream) and tide marks on the newly white painted walls. It's in patches along the bottom. We put a damp proof membrane under the laminate floor boards and underlay. I wonder if the laminate flooring has caused this? We've put more air vents along the bottom of the walls affected and on the chimney breast (this has an electric heater on it and appears almost completely sealed). There are no leaks or burst pipes etc.

Has anyone experienced anything similar or any ideas as to what could be causing the damp and how to treat it? Thanks in advance.

[ultimatehandyman]

I can't see the laminate flooring and DPM causing the problem. It is probably an underlying issue that has just surfaced.

You could do with a damp meter to check the interior walls for rising damp.