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25mm Rockwool RW5 Black Tissue Faced 2 Sides A1 Slab (pack of 8)

25mm Rockwool RW5 Black Tissue Faced 2 Sides A1 Slab (pack of 8)
25mm Rockwool RW5 Black Tissue Faced 2 Sides A1 Slab (pack of 8)
  • 25mm Rockwool RW5 Black Tissue Faced 2 Sides A1 Soffit Slab
  • Provides from 30 minutes up to 240 minutes fire protection
  • Used for structural elements such as concrete car park soffits
  • A1 class, non-combustible fire resistant stone wool insulation slab
  • RW5 Formerly ProRox® SL9 60 Thermal conductivity of 0.034W/mK
Estimated delivery:
In Stock
£ 269.88
Ex VAT: £ 224.90
  • Brand: Rockwool®
  • Model: 25mm RW5 Black Tissue x2
  • Weight: 10.88kg
  • Dimensions: 1,200mm x 600mm x 25mm
  • SKU: 25mm RW5 Black Tissue x2
  • Product code: P1-2801
  • MPN: 25mm RW5 Black Tissue x2

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25mm Black Tissue Faced Both Sides RW5 is a highly durable A1 class, non-combustible fire resistant resin bonded stone wool insulation slab, used for structural elements such as concrete car park soffits and similar applications.

Black Tissue Faced Both Sides Rockwool RW5 (Formerly ProRox® SL 960) is a high-density 100kg per cubic meter, rigid soffit insulation slab with a certified thermal conductivity (lambda value) of 0.034 W/mK.

The black tissue facings help to avoid the slab edges from showing as shadows through the perforated inner sheet and assists in preventing fibre migration (five times less fibre migration-bullet).

RW5 Insulation Slab 25mm x 600mm x 1200mm faced with black tissue on 2 sides can provide from 30 minutes up to 240 minutes fire protection to the underside of concrete soffits.

Rockwool RW5 (BTFx2) Slab works in two distinct ways to reduce noise, either by impeding the transmission of sound through an element of the structure or by absorption of sound at the surface.

These fire, thermal and acoustic Rockwool RW5 black tissue faced 2 sides insulation slabs are free of CFCs and HCFCs and will not encourage the growth of fungi, mould or bacteria.

The structure of the fibres in RW5 stone wool insulation slabs make them an ideal solution for use as a sound absorber with water repellent qualities of the insulation preventing moisture build up, damp and rot.

Rockwool RW5 with Black Tissue Facing on both sides is a robust long-lasting insulation made from renewable resources which will maintain high performance over the lifetime of the building.

RW5 Black Tissue Faced 2 Sides Slab works in two ways to reduce noise, either by absorption of sound at the surface or inhibiting its transmission.

ROCKWOOL RW5 Soffit Insulation Slab has achieved a Euroclass A1 fire rating and is capable of withstanding temperatures in excess of 1000°C.

The absorption coefficient achieved will vary according to thickness and density of the slab and application.




Thickness: 25mm

Width: 600mm

Length: 1200mm

Density: 100kg/m3

Pack Quantity: 8

Slab Coverage: 0.72m2

Pack Coverage: 5.76m2

Finish: Black Tissue Faced 2 Sides

R-Value: 0.70m2K/W

Thermal Conductivity: 0.034W/mK

Vapour Resistivity: Negligable, Water Repellent

Building Regulations: Class ‘O’ 

Fire performance: Euroclass A1 (non-combustible)


Black Tissue Faced Two Sides (BTFx2) Rockwool RW5 Soffit Slab Installation Guide:

 · When fixing a tile or modular system, it is advisable to start with a focus reference slab in the centre of the soffit with subsequent slabs being fixed working towards each edge.

 · The use of string lines or laser alignment equipment will assist in ensuring alignment and squareness of the installation.

 · If RW5 is installed into a concrete or steel composite deck, a pilot hold should first be drilled prior to the fixing being screwed into place.

 · RW5 Soffit Slabs should be fixed directly to the concrete soffit using Ejot DDS fixings with the Ejot DDT70 washer or similar.

 · Care should be taken not to over-tighten fixings to prevent damage to the slab surface.

 · For further information on fixing type and suitability for the substrate, please refer to the fixing manufacturer.

 · It is recommended that all black tissue faced slab joints should be staggered and tightly butt jointed.

 · Soffit insulation RW5 slabs should not be used for supporting light fittings or services.

 · Such installations should be supported from the concrete soffit.

 · Where penetrations occur, the boards should be cut locally to ensure a tight fit around the penetration.

 · Black Tissue Faced Slabs can be cut slightly oversized to ensure a tight fit under slight compression around the penetration.

 · Any small gaps that result from cutting can be infilled using the Acoustic Intumescent Sealant.


Black Tissue Faced 2 Sides RW5 SL960 Soffit Slab Health & Safety Regulations:

 · The safety of Rockwool stone wool is confirmed by current UK and Republic of Ireland health & safety regulations.

 · Rockwool fibres are not classified as a possible human carcinogen.

 · The mechanical effect of fibres in contact with skin may cause temporary itching.

 · Cover exposed skin during handling and installation.

 · When working in an unventilated area, wear a disposable face mask.

 · Clean working area using vacuum equipment.

 · Waste should be disposed of according to local regulations.

 · Rinse in cold water before washing.

 · Ventilate the working area if possible.

 · Wear goggles when working overhead.


*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 

Board covarage 5.76 m2
Colour Light brown ǀ Black
Density 100kg/m3 
Fire Protection (Resistance to Fire) from 30 up to 240 minutes
Length 1200mm
Material Stone Wool ǀ Black Tissue
Pack Coverage 5.76m2
Pack Quantity 8 slabs
Profile Square Edge
R-Value 0.70m2K/W
Size 25mm x 600mm x 1200mm
Thermal Conductivity 0.034W/mK
Thickness 25mm
Weight/m2 1.88kg
Width 600mm
Fire Classification Class 'O'
Vapour Resistivity Negligable, Water Repellent Slab
Slab Coverage 0.72m2
Building Regulations Approved Document B
Black Tissue Faced Yes, Two Sides
Coverage 5.76m2
Fire performance Euroclass A1 (non-combustible)
Finish Black Tissue Faced 2 Sides
Quantity 8 slabs per pack
Durability Insulation slab should last the lifetime of your building
Shipping method Articulated Vehicle ǀ Courier
Grade High Density Soffit Insulation Slab 100kg/m3
Sound insulation reduction Up to a factor of eight
Applications Structural elements such as concrete car park soffits
ETA Notification Yes
Features Fire Rated RW5 Soffit Slab (prevents fibre migration)
Manufacturer Rockwool RW5®

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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.
25mm Rockwool RW5 Black Tissue Faced 2 Sides A1 Slab (pack of 8)
25mm Rockwool RW5 Black Tissue Faced 2 Sides A1 Slab (pack of 8)
£ 269.88