Will the invisible penetration waterproofing agent corrode the pret floor heating pipes in the bathr

Your situation is complicated and complex, and simple is simple. If you want to solve it simply, I suggest you just knock off the floor tiles in the bathroom, do a new waterproofing, and then re-lay the floor tiles.

From what you said, it can be seen that you are quite knowledgeable, and the description of your family's situation is also very clear. In fact, I am not worried about the water in the bathroom that penetrates along the floor tile joints and then corrodes the floor heating pipes, but what I am worried about for you is that the infiltrated water will corrode the steel wire mesh. We all know that steel wire mesh is easy to oxidize, and then rust and corrode, which is likely to corrode the floor heating pipes that come into contact with it.

So you definitely come to the conclusion that waterproofing measures must be done.

So as for knocking off the tiles and redoing the waterproofing or directly using a penetrating waterproofing agent? This point is as you asked, to see if the waterproofing agent will have a corrosive effect on the floor heating pipe, I personally think there must be a slight corrosive effect. However, for the sake of accuracy, it is recommended that you ask the manufacturer in detail whether there is a corrosive effect on the plastic pipe, how much the corrosive effect is, and tell them the situation so that they can tell you whether your idea is feasible.

The last problem is that after the waterproofing agent dries up and is fixed, it is attached to the horizon layer and is not an independent individual, so whether the waterproof layer will crack depends on whether the horizon layer cracks. If it cracks, the waterproofing layer will break along with the horizontal.