I'm renovating my bathroom and I was planning on chasing copper pipe in to the wall for a shower and a heated towel rail and then tiling over it. However I'm concerned about either there being a bad joint and it leaking or things not lining up properly. So could I put braided metal hose in to the wall and the fill the cavity with fire foam? Am I right in thinking that this would be less likely to leak? Also does anyone know if this would comply with UK building regulations?