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90mm Rockwool External Wall DD Insulation Slab ǀ pack of 2

90mm ROCKWOOL External Wall Insulation DUAL DENSITY Slabs - Thin Coat Rendering
90mm ROCKWOOL External Wall Insulation DUAL DENSITY Slabs - Thin Coat Rendering
90mm ROCKWOOL External Wall Insulation DUAL DENSITY Slabs - Thin Coat Rendering
90mm ROCKWOOL External Wall Insulation DUAL DENSITY Slabs - Thin Coat Rendering
90mm Rockwool External Wall DD Insulation Slab ǀ pack of 2
  • Fire Rating: A1 Non-combustible
  • Breathable - Easy to handle and install
  • Excellent thermal and acoustic performance
  • Ability to withstand temperatures of up to 1000ºC
  • Can be applied to a wide range of substrates
Estimated delivery:
In Stock
£ 77.45
Ex VAT: £ 64.54
  • Brand: Rockwool®
  • Model: 90mm EWI
  • Dimensions: 1,200mm x 600mm x 90mm
  • SKU: 90mm
  • Product code: P1-951
  • MPN: 90mm Rockwool DD Slab

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90mm Rockwool DD External Wall Dual Density Slab is a façade thermal and acoustic insulation slab developed for insulated render systems in new build and refurbishment projects to prevent the spread of fire.

Rockwool DD is a high-performance, non-combustible stone wool slab used to insulate the walls of staircases, external walls of multi-family buildings, also as insulation from the side of an unheated room and underground garages.

The insulation slabs have achieved A1 class, which is the highest fire rating for non-combustible material. 

Rockwool insulation helps to prevent the spread of fire and can withstand temperatures up to 1000ºC.

Top-class Dual Density slabs are ideal for use with breathable polymer thin coat renders and can be placed on walls made of silicate, brick, block, reinforced concrete and ceramic blocks.

The boards are manufactured using 'dual density' technology, the outer surface of each slab features a clearly higher density than the underside.

This provides a firm and robust surface for the application of metal pin fixings and top coat render, while the resilient underside can accommodate unevenness in the substrate.

Once correctly installed, adjacent tightly-butted slabs will effectively 'knit' together to provide a sustained insulation layer, terminating thermal bridging caused by gaps in the insulation structure.

Complete external wall insulation made of ROCKWOOL Dual Density is highly durable and maintains its functional properties throughout the entire life of the building.

Stone wool insulation will work as effectively as the day it was installed - even after 50 years of use.

Rockwool insulation saves fuel costs and energy in use and relies on trapped air for its thermal properties.

Dual Density insulation is made from renewable resources and does not contain gases that have ozone depletion potential or global warming potential (ODP and GWP free).

Rockwool External Wall Slab for Insulated Render System is 97% recyclable! 




Width: 600mm

Length: 1200mm

Board Coverage: 0.72m2

Pack Coverage: 1.44m2

Density: 110kg/m3

R-Value: 2.49m2K/W

Thermal Conductivity: 0.036W/mK

Fire Rating: A1 Non-combustible


Key points:

 · Class A1, non-combustible material.

 · Thermal conductivity (λ - lambda value) of 0.036W/mK.

 · Vapour-permeable material.

 · Eco-friendly made from molten volcanic rocks.

 · Reduction of thermal energy consumption thanks to very good thermal insulation.

 · Reduction of thermal bridges thanks to the continuity of insulation.

 · Acoustic performance - reduce the impact of sound.

 · Durable and highly aesthetic façade insulation.

 · Suitable for new build and renovation.

 · Helps to effectively prevent the spread of fire.

 · Withstand temperatures up to 1,000ºC (1,800ºF).



 · Staircases

 · Multi-family buildings

 · Balcony loggias.

 · Sandwich walls.

 · External wall insulation systems.

 · Framed wall surfaces.

 · Solid brick and block walls.

 · Continuous outer layers of frame walls.

 · Cavity block and brick walls.

 · Cavity dense block walls.

 · Thin coat rendering.

 · Gaps in closed or ventilated three-layer walls.

 · Insulated render systems.

 · ETICS - External thermal insulation composite systems.


Health and Safety:

 · Wear eye protection, safety gloves and a mask!

 · Use a premium insulation adhesive to fix the slabs to the substrate.

 · Use a premium metal pin fixings to fix the slabs to the substrate.



 · Keep in a dark and dry place.

 · Avoid excess heat.

 · Avoid exposure to UV light.



 · BS EN ISO 9001:2008.

 · FM 02262.

 · ISO 50001:2011.

 · ISO 14001:2015.

 · Fire classification of A1 - EN13162.


*Further information may be found in our Downloads section.

Fairly easy access to all PDF files.

Datasheet ǀ Declaration of Performance - DoP ǀ BBA Certificate ǀ Installation Guide ǀ Certificates ǀ Brochure ǀ SPEC Sheet 


*Special Product - Non returnable cancelable.

Board covarage 1.44 m2
Colour Pale white
Density 110kg/m3
Length 1200mm
Material Molten volcanic rocks
Pack Coverage 1.44m2
Profile Square edge
R-Value 2.49m2K/W
Temperature resistance up to 1000ºC
Thermal Conductivity 0.036W/mK
Thickness 90mm
Weight 14.27kg
Width 600mm
Fire Classification A1 Non-combustible
Slab Coverage 0.72m2
Coverage 1.44m2
Application Temperature from +5 °C to +25 °C
Shipping method Articulated Vehicle ǀ Courier
Applications External Wall Insulation Systems
ETA Notification Yes
Features Thermal and Acoustic Insulation Slab
Manufacturer ROCKWOOL®

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We deliver insulation materials to Mainland UK only. Deliveries to Highlands, Northern Ireland, Isle of Wight etc.. might be possible at additional cost.
We offer free delivery on most of the orders above £300 (excluding VAT) (except special products - shipping cost via courier - products marked ''Request A Quote'')

Delivery of some insulation materials might be extended due to the current situation (Covid-19, stock shortages, allocations).
If you need materials quickly please contact us - we will do our best to help you source materials needed.

We do not deliver on weekends and bank holidays. Sometimes we can deliver on Saturdays - please check with us before placing the order.
If you need any further information please contact us tel. 02081910776

We can help to calculate price per m2 or linear meter (one meter in length) cost, please just contact us via phone 02081910776, email or live chat. Alternatively, you can work it out yourself quickly and easily: to get cost per meter square please divide price shown in orange area by ''Required area (m2)'' Example price of £28.80 divided by board coverage 2.88m2 = cost of £10.00 per m2.


No matter whether you choose a local installer or a national company, there’s a few tips to help you find the right installer for your home insulation improvements, such as asking for recommendations and making sure that they’re part of a certification scheme. This makes sure that they have the right skills and standards of workmanship to carry out the installation, and you can be sure that they know exactly what they are doing.


1. Thermal inspection picture in portfolio

It’s worth seeing a installer’s previous work. There’s no harm asking if you can see any properties nearby that they’ve installed insulation in. Best way would be to see Infrared Thermal Imaging Inspections. Thermal cameras spot small, but key changes in temperature in different areas of a house, identifying problematic areas that the human eye never could and some that a visual inspection could only hypothesize.

2. Reviews

Along with checking recommendations and previous work, finding reviews online can often be a great way to find out if they provide a good service or not. However, it’s best not to solely rely on reviews you may find or review websites, as there’s no controlling who writes them.

3. Compare prices

Comparing prices will also ensure companies can’t take advantage of you and give you a fair price. 

4. Word of Mouth

The best way to find a great insulation installer is through recommendations. Make sure you ask friends and family. They will most likely give you their honest opinion and can tell you from first hand experience.


Whether you require a wall, cladding, external wall, loft or floor insulation fitted, you can find and hire your local insulation installers from popular UK web pages. A simple internet search will return thousands of potential installers near your area.



We are the stockist of construction materials and related products for both trade and DIY from most recognizable brands in the UK like Cordek, RCM, Promat, Rockwool, Isover, Celotex, Xtratherm, Ursa, Low-E, Cedral, Kingspan, Dufaylite, British Gypsum, K-rend, Ecotherm, Iko enertherm, Kay-Metzeler, Terrawool to allow you to complete your insulation job on time at competitive prices and the highest standards.


Whether you are a large company or a DIYer, if you need a large amount of insulation materials, we can offer quantity discounts at the best prices. Please contact us and our friendly customer service will try to find the best and cheapest solutions for you. We value your time and we will try to deliver the products as soon as possible at a reasonable price to your construction site or house. The UK's leading insulation supplier near you and your needs. Price List available upon request.
90mm ROCKWOOL External Wall Insulation DUAL DENSITY Slabs - Thin Coat Rendering
90mm Rockwool External Wall DD Insulation Slab ǀ pack of 2
£ 77.45