The pipes feeding my shower have an odd arrangement. Hot and balanced cold plastic pipes come down from the loft into the shower space, go into the utility room next door, along the wall and into the garage. They then loop around, come back through the utility room, back into the same hole in the shower room and go to where the shower mixer bar is fitted.
The loop in the garage is two plastic elbows with a 50mm copper pipe between them. There are no isolation valves, check valves or any other form of fitting on the pipes - just a seemingly-unnecessary 5 meter long loop.
This has obviously been some effort by the original fitter - it would be far easier to feed the shower directly from the pipes coming from the loft. There is nothing functional in the pipework loop. So why have they done that?