The waste pipe from the handwash basin in our downstairs loo, runs 'horizonally' along a wall for about 2 metres, about 6 inches from the floor. To reduce visible pipework in the loo, we'd like to hide this pipe by putting it in a chase in the wall, then tiling over the top to conceal.
The wall in question is an exterior wall which was built only about 2 years ago, with nothing above except pitched tiles roof over loo and entrance porch. Inside skin is lightweight block (possibly 100mm thick 'Celcon'), with plaster finish. Outer wall is brick. Wastepipe is standard 32mm diameter white plastic (I think, but might be 40mm)
Please can anyone advise whether I can safely cut a chase in this celcon wall without problems? Will the wall fall down afterwards?!
TIA
D Green