So if you haven’t a chimney in the room where you want to fit your stove. Then why not create one?
Insulated twin wall flue is used where there isn’t an existing chimney. It’s a little larger diameter than flexible liner because it’s made with an inner and outer pipe, with layer of insulation between the two stainless steel pipes. External diameters range from 180mm to 200mm.
Twin wall flue is suitable for internal and external installation so you can either have it run up through your house, up the outside of a side wall. The regulations can be strict but there are generally plenty of options, if you want some advice just get in touch.