Another important factor will concern the amenities of a dwelling. These may cover variables like the existence of a bathroom, a balcony/terrace, special flooring or wall covering, an open fire, central heating, air-conditioning, special glazing and other noise or thermal insulation measures; the layout of the dwelling is also relevant.
Flooring products and wall coverings - measurement of emissions can be done, and thus a value can be declared by using prENV 13419 part 1-3 which gives a general harmonised method (part 1-2) for the determination of volatile organic compounds (VOC) from construction products.