I want to replace a radiator with a same size new one ( 600x800)and new valves. The problem is that there is only a limited access of 6" of pipe rising up to the rad through the floor and compression fittings need to be used on this pipe. It is not possible to lift floorboards to alter / reposition pipes beneath the floor. Even if I could, I wouldn't want to because the pipes are stainless and I am told they are also notorious for leaking if disturbed. I understand that the distance from wall may not be same and that the distance between valves may be slightly different. Even if flexibles were allowed I couldn't get them in unless I lift the radiator a few inches higher but lifting can easily be done. Can anyone suggest the best way to tackle the job? I thought of plastic pipe between the new valves and the old pipe using compression but is it flexible enough given there would only be about 3" of plastic. many thanks for your considerations, kev