Energy method for calculating the noise penetrating into flat rooms through walls

The noise state in buildings is a general process of sound energy distribution in the building volume. The sound energy emerging in separate rooms falls on enveloping structures of the rooms and penetrates to the adjacent volumes. In this case the enveloping structures of the noisy rooms become the sources of noise for other rooms. In public buildings flat rooms widely occur, in which the noise from technical rooms often penetrate. The authors observe the principles of evaluating indoor noise in a flat, which penetrates from adjacent premises through the walls. The method of calculating sound pressure levels in rooms is offered. The method takes into account the patterns of direct sound distribution from the flat noise source (wall) and the conditions of the reflected sound field creation in flat space of finite and infinite length. The direct sound energy distribution character is determined by geometric parameters of the wall shedding the noise. The method provides the desired calculation precision of the sound pressure levels