Situation: existing floor is okay(ish). Some damage due to environment and previous owners, looks cheap(ish), colour doesn't match new living room layout & theme. New floor is only 1cm (10.5mm) thick, and perfect for our needs. What would happen if the new underlay (2mm thick) plus the new floor is installed on top of the existing flooring? Beside the obvious loss of 1cm from the room. No skirting board installed yet (been removed in anticipation of the re-work).
Would it work and would have all the insulation benefits for which I am willing to sacrifice the 1cm loss from the room height for?