I have just moved into a Victorian terrace. There is a beautiful wooden door with a letterbox on the inside of the porch area. I guess it's original but im not sure. However there is also a upvc white door on the outside of the house that would have been the open porch area. I really don't like it but I presume they put it up as the wooden door is drafty. Can you improve original doors and draft proof them or will it always be inferior to the upvc? Or should I replace the upvc with a newer nicer door and still have two doors? Above the old door is a glass window too so that would allow cold air in too. Advice very welcome