Sealing of the bathtub

Hello! We are building a wooden prefabricated house and now the bathtub has been installed. The company did not waterproof the gypsum board back wall at all, installed the bathtub, and only sprayed sealant along the top edge of the bathtub. Shouldn't this wall be properly waterproofed on the gypsum board so that later, due to leaking joints or the faucet, water cannot penetrate and cause the gypsum boards to swell? The construction company says this is fine, allegedly the bathtub is sealed to the wall with silicone. But from the bathtub upwards, you can only see the gypsum board. We are totally uncertain and unfortunately have no technical knowledge ourselves and are at the mercy of the company. Thank you very much for any help. Regards hawaii2010

The wall will still be tiled, right? I think that's quite common, as it was done with you. You just have to be meticulous with the silicone joints and renew them after a few years if cracks form or the things become porous. If everything is installed correctly, there should be no problems. With us, it will be done the same way, the tiles are waterproof in themselves :)

In my opinion, that is not correct. Walls behind bathtubs and showers should usually be coated with sealing slurry before tiling, and not too thinly. In our case, this was done and even had to be redone because the inspector said it was insufficient.