Impact sound is the ability of the building to reduce noise, scratch noise, impact and shock from floors in adjacent spaces.
In most countries, including Sweden, there is a requirement for how much noise can be heard in an adjacent space, for example, and spaces can be found in homes, schools, care centers, etc. Standards also provide opportunities to classify a building in different audio classes so that the market itself can control the construction of spaces with better noise levels for those who wish. Step noise levels can now be a competitive asset for property owners.
A construction, ex. beam noise, step noise level in a laboratory measurement is described with its weighted normalized noise level Ln, w. The lower the value of the noise level, the better the design. What is also done is to look at the step sound improvement in relation to a reference beam. This mostly makes surface finishes, such as carpeting, installation floors or clean soundproofing materials. The step sound level or step sound enhancement is specified in decibels.
Laboratory measurement of step sounds is simplified so that you have two rooms usually on top of each other, but also next to each other. In between, there is a test surface, aperture, where you can build your construction, such as a beamed ceiling. The beams can be tested with various components in the construction together with different surface layers, floor materials. On the test surface, a step-noise machine is placed which is a machine of several weights in a row that is lifted and released in a certain order with a smearing sound as a result. The noise level is then measured in the non-step-free room. The level measured in the room will simplify the step noise level the structure has.
The standards we use and are accredited for current laboratory measurements of step noise are SS-EN ISO 10140-1: 2016, SS-EN ISO 10140-3: 2010, SS-EN ISO 707-1 and related requirements for measurement procedures and measurement room requirements in SS-EN ISO 10140-4: 2010, SS-EN ISO 10140-5: 2010.