How Does Sound Proofing Work?

Soundproofing is done to either block noise from entering a room or to block noise from leaving a room. Soundproofing works by using materials that either reduce or absorb sound. While sound usually cannot be blocked completely, substantial noise reduction is possible.

Music producer
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Recording studios use soundproofing not to keep sound in, but to keep unwanted sound out.

The Reason for Soundproofing

Reducing Sound

Thick permanent walls, temporary walls, foam, room dividers and curtains are among the materials that are used to reduce sound. Soundproofing materials for reducing sound are often made out of wood and fiberglass, but there are additional materials that can be used, as well. Forming an airtight barrier around the walls or curtains reduces sound by preventing noise from getting through the air holes. You cannot breathe in a totally airtight room, but you can reduce air spaces to minimize noise. One noise-reduction method commonly used is to build two walls or two doors with an airspace in between. The two doors or walls provide extra material to block sound, and the air space in the middle creates a sort of bubble that helps to block sound.

Absorbing Sound

One problem with reducing sound with thick walls or doors is that the sound can bounce off the surfaces of the room and create an undesirable echo effect.This issue is dealt with by using materials that absorb the sound. Dense foam is commonly used for sound absorption. Soft materials like foam absorb sound because the sound travels into the soft surface and gets reduced as a result. Sound-absorbing can be placed inside a wall or attached to the outside of a wall.

Areas of a Room to Soundproof

Sound can enter though doors, windows, thin walls, the floor or even the roof. When soundproofing a room, it is important to evaluate the room to see which areas need to be soundproofed. Stand in the room, listen and walk around to see where noise is getting in or out.


Rose Kivi

Rose Kivi has been a writer for more than 10 years. She has a background in the nursing field, wildlife rehabilitation and habitat conservation. Kivi has authored educational textbooks, patient health care pamphlets, animal husbandry guides, outdoor survival manuals and was a contributing writer for two books in the Uncle John’s Bathroom Reader Series.