We are installing a new bathroom. Have chosen mixer taps that fit to wall rather than to bath. As wall is only stud work it will need some reinforcement in case someone grabs the taps when getting out of the bath. From the back of the face plate to the end of the threaded water connection inside the wall is only 20mm. This has to accommodate the thickness of the wall tiles, the stud wall and the nut of the water connection??? 20mm is not long enough for this. Is there a secret way of doing it?