A room with a high nrc rating eliminates background noise and echoes to help clarify speech.
Floor material nrc.
00 absorbs very little sound while a 2 thick piece of silentfiber can have an nrc of 95 1 00 very absorbent.
Vinyl cork and rubber have a fairly high nrc rating.
For example an nrc rating of 75 means 75 of the sound energy coming in contact with that specific material is absorbed.
Simply put the sound is not reflected back into the room to create noise.
A material with an nrc of 0 75 would also be considered 25 reflective.
It has an stc rating of 44 and an nrc of 0 80 and can be added to walls floors and ceilings during or after construction.
Other helping nrc info.
The table below gives some nrc ratings for common building materials.
The nrc is the percentage of sound that a surface absorbs in other words hits a surface and doesn t reflect.
For example a concrete wall could be 0 to 35 absorptive.
Noise reduction coefficient nrc while stc and src indicate how well noise passes through different materials nrc noise reduction coefficient measures how well materials stop sound from reflecting how much sound they can absorb.
Carpet having an nrc rating of 40 50 has the highest nrc rating of any type of commonly used flooring.
For example a thick polished marble floor may have an nrc of.
Cellulose insulation is composed of 75 85 recycled paper fiber with the remainder being made up of fire retardant mater.
Carpet has an nrc rating of 40 50 and is the most efficient absorptive flooring material.
Nrc noise reduction coefficient measures the amount of noise absorbed by the material and not reflected.
If available it is always best to get the tested nrc rating from the manufacturer.
Typically the nrc rating of a material is viewed as a percentage.
Acoustical ceiling tiles are often tested in type e400 mounting which simulates a 16 inch deep plenum.
In addition nrc ratings are often provided based on a given assembly.
The nrc is highly dependent on the type of mounting which if not specified is usually a type a mounting abpma mounting 4 where the material is placed directly on the floor wall or ceiling.
A quick look at the pros and cons of flooring on the market today.
Theaters for example are constructed with a high nrc rating in mind.
It reduces the vibration resonance within a wall or ceiling absorbing damping and deadening sound.
Because of these ranges and the limitations of the nrc rating system it is highly recommended to have an acoustical professional analyze your particular space materials and installation methods.
For instance a carpet manufacturer may indicate an nrc rating of 50 but this rating may be for the carpet pad and sub floor it is not necessarily just for the carpet.
