Insulation for Timber Separating Wall

The primary purpose of a separating (Party) wall is to provide acoustic separation for airborne sound between two adjacent dwellings, thereby improving the acoustic comfort of those living within both dwellings. The minimum permitted acoustic specifications are defined by Approved Document E (England & Wales) and Section 5 (Scotland), although it is often recommended to improve on this where possible.

One of the methods to demonstrate achieving this is to use Robust Details, alternatively an acoustician can be tasked with verifying the design of a separating floor. The insulation of choice for timber separating (Party) walls is typically a glass mineral wool roll.

ISOVER Timber Frame Party Wall Roll can be installed as part of the separating (Party) wall construction within the central residual cavity between the two adjacent lines of studwork to provide the level of sound reduction required according to Approved Document E (England & Wales) and Section 5 (Scotland).

Another important benefit of certain specifications and then correctly installing insulation in the residual cavity of a separating (party) wall is that it can help contribute to a zero effective U-value in SAP* for this wall, reducing energy usage and making compliance with Building Regulation easier.

*as per TFPWR PDS on zero-effective U-value in SAP

_{^{The building detail is for illustrative purposes only. It does not constitute advice and should not be relied upon.}}

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Insulation products to consider

Product Name	Thickness Range	Sizes	Lambda	BBA
ISOVER Timber Frame Party Wall Roll	50mm - 100mm	Width 1200mm Un-split, Length 6000mm - 12000mm	0.036 W/m.K
ISOVER Timber Frame Roll 32	90-140mm	Width 2x570mm, Length 2700-4200mm	0.032 W/m.K
ISOVER Timber Frame Roll 40	90-140mm	Width 2x570mm, Length 6500-10130mm	0.040 W/m.K
ISOVER Timber Frame Batt 40	90-140mm	Width 570mm, Length 1175mm	0.040 W/m.K
ISOVER Timber Frame Batt 35	90-150mm	Width 570mm, Length 1175mm	0.035 W/m.K
ISOVER Timber Frame Batt 43	90-140mm	Width 570mm, Length 1175mm	0.043 W/m.K
ISOVER Timber Frame Batt 32	50-140mm	Width 570mm, Length 1175mm	0.032 W/m.K
ISOVER Timber Frame Roll 35	90-140mm	Widths 2x570mm, 3x400mm (140mm only), Length 4000-5300mm	0.035 W/m.K