I have spent some time lagging a mains cold water pipe that runs through a cold cellar I am renovating. previously a great deal of water was condensing on the pipe work an dripping onto the floor. I used high-quality Armaflex insulation, and sealed the slits and joints on this tightly with black electrical tape. However, although the situation is much better, and does not seem to be actually dripping now, if I run my hand along the insulation of the horizontal pipe, I can still feel a good amount of wetness, which is actually forming on the insulation now.
Could this be because I have used too much electrical tape, which is now forming another cold surface? I have used a lot in places. Should I put more insulation on to cure the problem?