Glass Mineral Wool - Earthwool Masonry Party Wall Slab


Party separating walls


Glass Mineral Wool


Earthwool Masonry Party Wall Slabs are non-combustible Glass Mineral Wool slabs, manufactured using our revolutionary ECOSE® Technology and are designed for use in masonry separating (party) walls providing a full-fill insulation solution which is installed as walls are being built.


  • Excellent thermal  performance 
  • Fully filling the party wall cavity allows a zero effective U-value to be claimed in SAP
  • Non-combustible A1 Euroclass Reaction to Fire classification
  • Excellent sound absorption 
  • Suitable for use with a range of constructions registered in the Robust Details Handbook 
  • Slabs are sized to fit between wall ties and knit together at joints



Thickness (mm)Length (mm)Width (mm)Euroclass Reaction to Fire ClassificationFacingArea Per Pack (M²)Area per Pallet (M²)

Robust Details

Robust DetailMinimum Cavity WidthBlock TypeBlock Density (kg/m³)FinishesParge CoatZero U-Value
E-WM-11100mmLightweight Aggregate1350-1600Plasterboard on dabsYesYes
E-WM-16100mmDense Aggregate1850-2300Plasterboard on dabsYesYes
E-WM-175mmDense Aggregate1850-2300Wet plasterNoYes
E-WM-275mmLightweight Aggregate1350-1600Wet plasterNoYes.
E-WM-375mmDense Aggregate1850-2300Plasterboard on dabsYesYes
E-WM-475mmLightweight Aggregate1350-1600Plasterboard on dabsYesYes
E-WM-575mmBesblock Star Performer1528Plasterboard on dabs on cement renderYesYes
E-WM-675mmAircrete600-800Plasterboard on dabs on cement renderYesYes
E-WM-1075mmAircrete600-800Plasterboard on dabs on cement renderYesYes
E-WM-11100mmBesblock Star Performer1528Plasterboard on dabsYesYes
E-WM-1275mmPlasmor Aglite Ultima1050Plasterboard on dabsYesYes
E-WM-1375mmAircrete600-800Plasterboard on dabs on cement renderYesYes
E-WM-18100mmDense Aggregate1850-2300Wet plasterNoYes
E-WM-19100mmBesblock Star Performer1528Plasterboard on dabsYesYes
E-WM-19100mmDense Aggregate1850-2300Plasterboard on dabsYesYes
E-WM-19100mmLightweight Aggregate1350-1600Plasterboard on dabsYesYes
E-WM-21100mmLightweight Aggregate1350-1600Wet plasterNoYes
E-WM-22100mmLightweight Aggregate1350-1600Plasterboard on dabsNoYes
E-WM-22100mmPlasmor Aglite Ultima1050Plasterboard on dabsNoYes
E-WM-25100mmWienerberger Porotherm850-950Plasterboard on dabsYesYes
E-WM-26100mmBesblock Star Performer1528Plasterboard on dabsNoYes
E-WM-2975mmWienerberger Porotherm850-950Plasterboard on dabsYesYes
E-WM-31100mmH+H Celcon Elements575Plasterboard on dabsNoYes
E-WM-3275mmLightweight Aggregate1350-1600Plasterboard on dabsNoYes

* Partial sheathing of the cavity faces of the separating wall for structural reasons is permited but the cavity width must be 50mm including sheathing (Timber Frame Party Wall Slab only)

Certification & Memberships

Eurofins Gold
Green Guide Rating A+
CE Marking
TÜV Nord
Robust Details


We care for the people who make our products, the people who use them and the world we all depend on.

 Whilst we are dedicated to supplying sustainable high performance insulation solutions for enhanced energy efficiency in buildings, we also continually strive for improvements in our manufacturing and supply chain operations so to improve quality and minimise our impact on the environment. All Knauf Insulation production locations have state-of-the-art manufacturing equipment and meet the highest quality standards as well as they are supported by an ongoing research and development program. All of our products including Earthwool Masonry Party Wall Slab are sustainably manufactured.

At Knauf Insulation, we have 7 key sustainability considerations:

  • to conserve natural resources
  • to reduce the evironmental effects of our own processes
  • Treating people fairly, along the supply chain
  • Delivering our products efficiently
  • Building a comfortable and healthy indoor environment
  • Performance reporting
  • Recognition
ECOSE® Technology

ECOSE® Technology is our revolutionary sustainable bio-based binder used in the manufacture of all of our glass mineral wool products, and the majority of our rock mineral wool products. invented nearly 10 years ago, it is not only unique, but very much central to our sustainability strategy.  Our ECOSE® Technology is present in Earthwool Masonry Party Wall Slab and is just another key benefit of our products.

ECOSE® Technology has 5 key benefits

  • A natural binder
  • A lower embodied energy
  • Proven durability
  • Optimum indoor air comfort
  • Easy to handle

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