Strutt|Building Acoustics|Facade Noise Break-In calculates the noise break-in through a building facade and inputs it into the active row of the worksheet.
Strutt calculates either the direct or reverberant component of the noise break-in, toggled by an option button on the user form. The outdoor sound pressure level is the incident level at the facade (i.e. with NO facade correction)
The direct component is calculated by:
`L_(p,dir In) = L_(p,ext) + TL + 10log_10(S) + Delta L_("dist")`
Strutt provides two options for calculating the reverberant component.
For low-moderate absorption in the receiving room, traditional diffuse field theory gives:
`L_(p,rev In) = L_(p,ext) + TL + 10log_10(S) - 10log_10(A) + 6`
For rooms with high absorption:
`L_(p,rev In) = L_(p,ext) + TL + 10log_10(S) - 10log_10(A) + 3`
where:
`TL` is the transmission loss of the partition (negative sign convention)
`S` is the total area of facade considered in the TL (m²)
`A` is the area of absorption in the receiving room (m² sabin), back-calculated from the reverberation time (`RT`) and volume (`V`) of the room by `A = 0.161V//RT`