ᐅ Underfloor heating leaking? Is moisture rising up the wall?

Hello everyone,

for about six months now, we have noticed cracks forming in the walls at the lower part of the basement hallway. At first, we thought these were settlement cracks, but gradually we suspect moisture might be the cause. Has anyone experienced something similar? From our perspective, the only possible cause could be the underfloor heating. Or do you think it could be related to the dryer or washing machine in the adjacent room?

Best regards,
TT

It definitely looks like water damage, but I can’t tell from what just by guessing. However, if you don’t need to refill any water in the underfloor heating system, I would rather suspect the washing machine.

Is the underfloor heating losing water? There is only about ±100 liters (±26 gallons) in total, and even if 1 liter (0.26 gallons) is missing, it can cause problems. This looks more like rising damp. Possibly a faulty horizontal damp proof course.

Is it only on the wall near the washing machine or somewhere else as well?

At the moment, it is only on the wall and is slowly developing on all four walls in front of the utility room. Inside the room itself, everything is dry.

That looks like something different. If the pressure in the heating system does not drop, it could also be a leaking water pipe or moisture from outside.