I am installing a concealed shower valve in a stud wall. It has at present a exposed valve fitted. All pipework is 15mm Hep20. Where is the best position to fit isolators (full bore i presume?) regarding access? Also, are the Hep20 fittings reusable or do you cut them off and replace with new? Do you have to use same or can you mix and match fittings including using copper as long as i use the correct inserts?
Many thanks in advance,