A common way to construct Cross Laminated Timber (CLT) dwellings is to mount the floor slabs continuous over several apartments, thereby reducing the number of CLT elements and work time with the crane on site. There are some crucial acoustic factors to consider if you are thinking about this route. CLT is sensitive to flanking transmission in the middle frequency range from about 125-160 Hz and upwards. If CLT elements are mounted between apartments and are exposed within the dwelling, the resulting sound insulation will not fulfill Swedish requirements. The resulting sound insulation R´w will likely be in the 40-50 dB range and not 52 dB as it should be. A common way to solve this issue is to install a resilient ceiling, and the solution can be optimized in different ways depending on the rest of the structure.