ETICS, external wall, clinker, interior, exterior

Separating Party Wall Insulation

ROCKWOOL party wall insulation can reduce thermal transmission in detached properties and flats.

Made from natural stone wool, our products help to regulate temperatures and reduce the impact of noise from neighbouring properties.

Find out how our range can boost the energy efficiency of your project

Why do we need party wall insulation?

Separating party walls are the dividing walls between two attached properties. They are constructed from solid materials, such as bricks and concrete blocks, or built out of a framed wall construction, using wooden studs or metal frames.

There is usually a gap between party walls called an air cavity, which separates the buildings. Hot air can seep into this cavity, through edges that are exposed to the elements outside, while cool air rises and escapes the building.

This heat gain can drive up cooling bills and create a less energy efficient home. Noise can also be an issue, as sound can easily travel through this hollow space. The increased amount of hot air flowing into a building can make the occupants uncomfortable1.

Party wall insulation fills the gap in-between, ensuring cool air and sound are captured and contained – improving acoustic and thermal performance.

High-quality insulation helps to:

  • Adequately soundproof walls
  • Improve energy efficiency
  • Raise fire resilience2

Separation walls can substantially increase the acoustic performance, especially when it is designed and built as a wood or metal-framed construction.

Roger Peeters

ROCKWOOL Group Product Manager

Calculator and savings

To work out the amount of insulation you’ll need, measure the length and width of the space you’re installing in and multiply – this will give you the m² area of the wall.

It’s also helpful to know the depth of the cavity wall space. This will determine what insulation thickness you require and how many layers you’ll need.

Use our ROCKWOOL U-value calculator to determine the thermal performance of the building’s walls and possible cost savings. For more details on technical specifications, visit our ROCKSPEC Specification Toolkit.

applications, facade, internal walls, how to
With a range of dedicated products for party wall applications, ROCKWOOL insulation meets specific needs such as good sound insulation and high fire resistance.

Roger Peeters

Global Product Manager, ROCKWOOL Group

Case studies

The challenge

The DUO Residences twin tower development in Ophir-Rochor, Singapore, involved construction of 660 luxury flats in one tower, while the other included a five-star hotel, office and retail units.

Architects were keen to reduce noise transfer between luxury units and penthouses. They also wanted to increase thermal performance.

The solution

ROCKWOOL insulation was chosen for separating walls, thanks to its excellent sound absorption qualities.

Fire resilience was another crucial factor. Stone wool not only allows walls to ‘breathe’ by letting air pass through, boosting air quality, but also withstands temperatures of up to 1000°C.

The results

  • Less noise travelling between residences
  • Comfortable indoor temperatures
  • Safer environment for residents
Marina One multi-purpose complex, Singapore, towers, urbanisation, indoor comfort, health and wellbeing, insulation, high-rise, quiet, mixed use, city, skyscrapers
DUO Residences is a Green Mark Gold Plus-rated building, and we’re proud to provide insulation solutions that enrich the lives of residents.

Alex Low

Country Sales Manager, ROCKWOOL Singapore

Sustainability and energy efficiency

ROCKWOOL party wall insulation is manufactured in an environmentally-friendly way.

We use sustainably-sourced diabase rock to create our stone wool solutions9. More than 38,000 times the amount used to manufacture ROCKWOOL products is generated naturally each year10.


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Financial support

Please check with your local government body for schemes which mean you could be eligible for financial support or refunds, especially in the case of renovations.

Energy Efficiency, Key, Keyboard, Button


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