Why is sound insulation between dwellings in renovated housing not upgraded like other qualities?

In Europe (EU-28), about 40% of the inhabitants live in flats in multi-family housing. According to social surveys in several European countries, many people in multi-family housing are annoyed by neighbour noise, which is considered a health problem. To protect health, building regulations in most countries specify minimum requirements for sound insulation in new housing. However, national acoustic regulations were typically implemented in the 1960’es or later. About half of the European housing stock was built earlier and in most cases far from fulfilling the present national regulations, depending on the construction types, which vary across Europe and over time.
Renovation of housing has been quite extensive during the last decades. Typically, renovation and upgrading of housing have included repair or replacement of roof, windows, installations, kitchen, bath, balconies etc. and with strong focus on energy savings. Although no registrations, it’s the impression among acoustic experts that renovation very seldom includes improvement of sound insulation between dwellings. There are a number of reasons for not upgrading or even considering upgrading sound insulation, e.g. lack of regulatory policies, lack of acoustic issues on check lists, lack of knowledge or simply lack of attention, implying that upgrading is opted out, before even evaluated on equal terms with other improvements.
The paper will discuss the above issues, describe examples from selected countries in Europe about efforts to change in a direction with acoustic issues taken into account. Furthermore, suggestions for joint efforts to improve the situation will be provided.