Regulation and compliance with performance standards Sound Insulation Regulation and compliance with performance standards BUILDING REGULATIONS (2000) AD Part E, Resistance to the passage of sound

BUILDING REGULATIONS Part E, Resistance to the passage of sound For dwellings the sound transmission includes flanking sound. Level Difference D = L1 – L2 Area of wall not important but the level must be adjusted to account for variations in reverberation time Standardised Level Difference DnT = L1 – L2 + 10log(T/0.5) L1 L2 Flanking Sound

WIEGHTED STANDARDISED LEVEL DIFFERENCE DnT,w (or WEIGHTED TRANSMISSION LOSS, Rw) The standardised level differences are plotted on a graph as shown below. The value of the curve at 500 Hz is taken and this is the rating for the wall (or floor). This rating is the Weighted Standardised Level Difference, DnT, w If we apply the same method to lab tests and plot ⅓ octave R values we get the weighted transmission loss, Rw Standardised Level Difference (dB) 1/3 octave bands 100 125 160 200 250 315 400 500 630 800 1k 1.25k 1.6k 2k 2.5k 3.15k Reference Curve DnT,w Or Rw Sum of adverse deviations = 28.3 dB

Impact Sound Transmission Similarly for impact sound Here the impact sound pressure level, L is measured, and the Reverberation Time in the receiving room Corrected for Rev. Time Ln = L – 10lg(T/0.5) L Tapping m/c Flanking

LnT,w is the weighted normalised impact sound level The Ln’s for all 16 bands are plotted as before and then a weighting curve is fitted to the data in a similar way to before except that the curve is a different shape as shown below. LnT,w is the weighted normalised impact sound level 500 Hz LnT,w (dB) Weighting Curve

ADE Performance standards

ADE Compliance Demonstrated by pre-completion testing, or alternatively By means of using robust details Robust details are high performance separating walls and floors deemed sufficiently reliable so as not to need the check provided by pre-completion testing.

Robust Details A method of compliance with AD Part E for housing developers operated by Robust Details Ltd – ‘not for profit’ co. Avoids requirement for pre-completion testing sites registered with Robust Details Ltd developer adopts strict QA procedure, check lists etc. RDL monitor procedures for construction quality RDL test a proportion of constructions, when failure indicates a fault in the detail, rather than the builder

SOUND INSULATION Practical Issues

BASIC REQUIREMENTS (Walls) Multiple layers more effective than a single layer of the same mass for airborne sound insulation = Layers must be isolated (on separate frames) Air gaps must include acoustic absorption 3000mm concrete mass 6400 kg/m2 2 x 3 layers of plasterboard with 400mm air gap mass < 150kg/m2

Typical performance of panels Weighted transmission loss, Rw for plasterboard panels. Remove 2 x plasterboard inside layers Basic Stud wall Double stud wall with absorption Add 2 x plasterboard to outside layers Remove 1 x plasterboard inside layer Add Absorption Rw = 33 dB 36 dB 40 dB 50 dB 57 dB 63 dB These values would only be achieved in the laboratory – no flanking!

Coincidence dips for glass 2kHz 600Hz

Coincidence dips for boards

Double walls—mass/air/mass Block wall with resilient bars and plasterboard Low frequency mass/air/mass resonance Note that the bare block wall is better at low frequencies than the same wall with an extra layer of plasterboard on one side – this is due to resonance.

Typical Constructions (walls) Wall ties allow vibration to cross the cavity

Typical Constructions (walls)

Joint Details Fully built-in Cavity stop

Edge Details

BASIC REQUIREMENTS (Floors) Floors have additional requirements to prevent impact sound being transmitted. This is achieve by either, or a combination of: Soft resilient surface layer Incorporated resilient layer and floating floor Separate ceiling layer

Typical Constructions (Floors)

Typical Constructions (Floors)

Ceiling Layers BEST WORST

Joint and Edge Details

Acoustic Timber Floor

High Insulation Wall System

Multiplex Cinemas 3 layers of plasterboard 5 x 100mm mineral wool 800 mm

Resilient Connectors Frames use “acoustic” braces (rubber isolation block to prevent transmission of vibration)

High Performance Foam & Vinyl Uses a sandwich construction to achieve good sound insulation by a combination of: "absorption-damping-decoupling“

REMEDIAL TREATMENTS

Flat Conversions (Walls)

Flat Conversions (Floors)

Flat Conversions (Floors)

Flat Conversions (Stairs)