walk-in shower

Hello Frank. We have already met in one of the other forums here. The bathtub must be placed on the floor slab/concrete ceiling for load transfer! Trying to level the screed, which lies on insulation layers, by grinding or milling is pointless! Because with reduced thickness, the load-bearing capacity of the screed also decreases. So how should one proceed? The solution is simple: First, you need the measurement of how much the screed needs to be notched afterwards. It must be cut out to the necessary extent. This is unproblematic, especially since at least one side adjoins the wall! On the execution date (choose only a cutting technique with good dust extraction!!!), you will commission the sanitary installation company that installed the underfloor heating to turn off the heating and depressurize the system. They must also bring material to inevitably reconnect heating elements cut during the screed removal. The screed section will be cut out, the damaged heating elements reconnected, water refilled in the heating system, and then everything will continue as usual! Floating screeds in residential construction are designed for a vertical surface load of about 150 kg/m². The edge areas are subject to higher stress than the center areas. With a filled bathtub and occupants, 150 kg/m² is quickly exceeded. The screed can (and this is realistic) break under the stress if the bathtub is placed on the "floating screed." The damage scenario mentioned here is real – I can confirm this from my own professional experience. --------------------------- Best regards: KlaRa

, no, this is not a bathtub but a shower tray; the plumber just forgot to lay the adapter board before the screed, then the tray would have sat 1.5 cm lower, now it lies on top. The heating is about 4-5 cm lower. That means if the board had been in place, the stability would also be there, but I have to discuss that with the plumber; I am not going to risk the warranty now, I just wanted to know if it is possible to remove it afterwards. Best regards, Frank

Hello Frank. I simply misunderstood the term "Duschwanne". But even with a shower tray, the installation area in the screed should be notched out. One of the fundamental questions is also: "What was originally required as part of the screed work?" Was the lowering (actually not permissible according to screed standards 13813 and 18353) commissioned? If YES, then the notching would be a classic rectification, free of charge for the client. Surely no legal dispute is needed for that! But no matter what: The (technical) problem is easily solvable! If it is a factory-made, i.e., prefabricated shower tray, then the connection of the waterproofing (to the surface waterproofing of the screed) is certainly already intended and therefore unproblematic. If it is not intended, there are also solutions here! You just have to know technically what you are doing. However, the shower tray should stand on the concrete ceiling or slab, since a screed reduced in thickness on the insulation layer will not bear these loads, even if they only amount to 1kN, without future risk! Because the shower tray stands on the edge of the screed, and the internal structural stresses at point loads due to bending moments are quite high there. The shower trays are supplied with height-adjustable locks, so that would also be technically easily solvable. It would be different with a craftsman-built shower tray, for example constructed using slope plates. Although that would also be solvable, one must definitely observe some things to avoid loud complaints later on. --------------------- Best regards and good luck: KlaRa