The paper presents a design process related to sound insulation of a small mechanical workshop for storing eccentric presses, which is located in a densely populated housing estate. Starting from the theoretical model of acoustic insulation power of a single solid partition, a complex partition and a multi-layer partition, the acoustic insulation power of the walls and the ceiling in the workshop was determined. The results of calculation of workshop isolation coincide to a great extent with the experimental results of measuring noise levels. Key words: noise, mechanical workshop, sound insulation