How is STC calculated?

How is STC calculated?

STC is calculated by taking the Transmission Loss (TL) values tested at 16 standard frequencies over the range of 125 Hz to 4000 Hz and plotted on a graph. If your wall graph is closest to a standard STC 35 curve, your wall is said to have an STC rating of 35. Adding Green Glue to boths side of a wall.

How is sound transmission class determined?

STC ratings are measured using a uniquely designed scale where the higher the number is, the greater the ability of the measured structure or material to reduce sound transmission (i.e. better soundproofing qualities).

What is the difference between STC and Fstc?

In practice, the Sound Transmission Class (STC) of laboratory samples represents optimum conditions, and is rarely achieved in actual construction. FSTC is a function of background noise levels, room volumes, surface areas, sound absorption values, and spectral content of the sound source.

How is the sound transmission class ( STC ) measured?

The Sound Transmission Class (STC), measured in decibels, is used to measure building material’s ability to absorb sound. The STC can be used to measure sound absorption for both external building walls and internal walls in single and multifamily structures. The STC is measured by positioning a representative

How can insulation increase the sound transmission class?

Installing absorptive insulation, for example fiberglass batts and blow-in cellulose, into the wall or ceiling cavities does increase the sound transmission class significantly. The presence of insulation in single 2×4 wood stud framing spaced 16″ (406 mm) on-center results in only a few STC points.

How to improve the sound transmission class of a partition?

There are many ways to improve the sound transmission class of a partition, though the two most basic principles are adding mass and increasing the overall thickness.

When was the sound transmission class first introduced?

It is especially important in commercial construction. The sound transmission class was first introduced in 1961 and has since become the standard single-number metric to describe sound blocking materials. People often mention NRC and STC ratings in similar contexts, but they are slightly different rating systems.