Apart from Green Building Store, Internorm and Rationel can anyone recommend any other suppliers of triple glazed PH rated windows? Ideally you have installed yourself and can speak from experience in terms of dealing with the company/cost etc? Thanks I should say that I am particularly interested in any Lift and Slide doors that have low profile frames but are still passive rated. For standard windows this is less of an issue. Also any tips on PH rated entrance doors would be useful t