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Many houses have mats on the floor because of the noise between
floors in the apartment. Especially in homes with children, thick mats are sometimes laid to reduce the noise between floors even a little, and I have seen how effective this actually is.

This is Hyemi Lee.

<Reporter>
I made a noise like dragging a chair upstairs in
my apartment.

When measured in the lower house, it takes 80 dB, which is equivalent to light noise.

When I laid down a 4 cm thick mat that is commonly used in the home and measured it again, the noise value was reduced to 40 dB, which was halved, so it was almost inaudible.

[Hongseok Yang / Senior Researcher, LH Land and Housing Research Institute: It may vary depending on the type of mat, but it appears to be reduced by up to 20dB in actual houses.]

What about the heavy impact sound, which is the heavy noise that occurs when children run or adults walk on their heels?

The change from before the installation of the mat is not significant, and the resonance is transmitted as it is.

[Hongseok Yang / Senior Researcher, LH Land and Housing Research Institute: Most of the noise in the low-frequency band is transmitted through the floor or wall by vibration, so it can be seen that the reduction effect is limited.]

However, on both sides, even if the mats were laid 2 or 4 thick layers, the figures were similar.

This means that the effect varies depending on the type of noise, and the thickness of the mat doesn't really mean much.

To solve interfloor noise, it is important to increase the thickness of the concrete slab, which is the bottom of the construction stage.

It has been reported that a 1 cm thicker slab will also reduce noise by 1 dB.

As a result, the thickness of the slab, which was 90 cm in the 15s, has been increasing steadily and has recently increased to 25 cm.

Increasing the performance of cushioning and finishes on top of the slab is also a great help in reducing noise.

However, this method has the limitation that it is difficult to apply it to existing houses.

(Video Interview: Joo Yong-jin, Video Editing: Won Hyung-hee, CG: Eom So-min, Screen Credit: Samsung C&T, Hyundai E&C)