Danish Health and Morbidity Surveys representing the population show that ~36% of people in multi-storey housing are annoyed by neighbour noise. National building regulations have existed since 1961 and included sound insulation limits, but complaints to housing organizations and builders appear for both old and new housing. A detailed analysis of national survey results shows that for occupants in multi-storey housing, a strong association exists between self-reported neighbour noise annoyance and various health issues. Building constructions have changed over time and consequently acoustic performance. The Danish standard DS 490 has six acoustic quality classes A-F representing housing built from before year 1900 until now, class C being minimum for new housing. Acoustic quality is invisible. However, the purpose of classification is enabling "visibility", but such information is typically unavailable. With mandatory acoustic classification for new and renovated dwellings, negative "surprises", when moving into new/renovated apartments could be foreseen. While prospective buyers and tenant organizations support acoustic labelling, strong resistance appears from e.g. real estate agents, and contractors. The paper presents advantages of acoustic quality transparency as well as resistance and also provides suggested steps towards implementation to the benefit of people moving to new places or understanding their current situation.