Planitherm Glass – Buyers Guide – MPN Windows Cardiff CF5. Installing Planitherm a new generation of energy saving window glass in Ely, Caerau, St Fagans, Culverhouse Cross, Canton, Leckwith, Fairwater, Danescourt, Llandaff, Riverside, Wenvoe, Peterston Super Ely, St Georges Super Ely, Michaelston, Cardiff CF5.