Loam (rammed earth) and timber may be the oldest materials in use. In timber buildings, loam mass layers may well be a good and sustainable solution for acoustics and vibration comfort. In this research we’ll focus on the application of loam as vibrational compression layer on CLT floors. How can the loam layers be made, how quickly do they harden, how stiff does the connection need to be? All questions that need to be adressed in a experimental and design research.