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30mm Foil Faced RS45 Rocksilk Knauf Insulation Slab 45kg ǀ pack of 16

30mm FOIL FACED RS45 Knauf Rock Mineral Wool Building Slab - 45kg density
30mm Foil Faced RS45 Rocksilk Knauf Insulation Slab 45kg ǀ pack of 16
  • FOIL FACED Slab - Odourless, Rot Proof, Non-Hygroscopic
  • Class ‘O’ to the Building Regulations - Euroclass A1
  • Density: 45kg/m3 - Excellent thermal and acoustic properties
  • Class 1 Surface Spread of Flame - Non-combustible
  • Durability: do not sustain vermin and will not encourage the growth of fungi, mould or bacteria.
Estimated delivery:
In Stock
£ 442.92
Ex VAT: £ 369.10
  • Brand: Knauf®
  • Model: 30mm Foil Faced RS45
  • Dimensions: 1,200mm x 600mm x 30mm
  • SKU: 30mm FF
  • Product code: P1-1069
  • MPN: 30mm Foil Backed RS45 Slab

Options available

30mm Foil Faced Rocksilk RS45 Knauf Insulation Slab is a standard density (45kg/m3) non-combustible rock mineral wool foil backed building slab with a great fire performance classified as Euroclass A1, suitable for use in multiple applications.

Knauf RS45 1200mm x 600mm rocksilk foil backed slab provides outstanding thermal and acoustic performance for both new build and refurbishment projects.

These odorless, non-hygroscopic, and rot proof slabs are free of CFCs and HCFCs and will not encourage the growth of fungi, mould or bacteria.

Knauf RS45 Building Slab comprises a high density rock mineral wool core which is foil faced on one side.

Rocksilk RS range is a high-efficiency insulation with a certified lambda value (thermal conductivity) of 0.035W/mK.

RS45 foil faced slab is manufactured with a density of 45kg/m3, designed for use in a variety of applications including internal partitions, timber and metal studs, and in between timber rafters and floor joists.

Knauf building slabs have excellent sound absorption characteristics providing high levels of sound reduction.

Rocksilk RS45 foil slab is easy to cut and shape with a large bladed knife or saw.

Insulation products made with ECOSE Technology contain no formaldehyde binder, dye or artificial colours.

RS45 Building slabs are also Zero ODP and Zero GWP which makes them more eco-friendly material.




Width: 600mm

Length: 1200mm

Pack Quantity: 16

Slab Coverage: 0.72m2

Pack Coverage: 11.52m2

Finish: Foil faced one side

Density: 45kg/m3 

R-Value: 0.85m2K/W

Thermal Conductivity: 0.035W/mK

Vapour Resistivity: 5.00MNs/g.m.

Surface Spread of Flame: Class 1 

Building Regulations: Class ‘O’ 

Fire performance: Euroclass A1 (non-combustible)


Key points:

 · Composite foil faced on one side.

 · Formaldehyde binder free.

 · Excellent thermal performance.

 · Non-combustible material - Fire classification.

 · Single slab can be used for variety of applications.

 · Excellent sound absorption characteristics provide high levels of sound reduction. 

 · Multi-purpose product range which can be used to insulate a wide range of applications on site.

 · Manufactured using revolutionary Knauf ECOSE® Technology.

 · A+ BRE Green Guide rating.

 · Thermal conductivity (λ - lambda value) of 0.035W/mK.

 · Fire Performance - Euroclass A1 to BS EN ISO 13501-1.

 · Free from CFCs, HCFCs

 · Odorless, non-hygroscopic, and rot proof product.

 · Do not sustain vermin.

 · Available in a wide range of densities. 

 · Easy to cut with a large bladed knife or saw.

 · Free of dye or artificial colours.



 · Multi-Application.

 · Ground floors.

 · Internal floors.

 · Separating floors.

 · Fabrication.

 · Pitched roofs at rafter level.

 · Internal walls.

 · Acoustic partitions.

 · Light steel frame walls.

 · Timber frame walls.



 · Eurofins Gold.

 · A1 Euroclass Fire Rating.

 · CE Marking.

 · TÜV Nord.

 · Robust Details.

 · Green Guide Rating A+ - B.


*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 11.52 m2
Colour Brown ǀ Silver
Density 45kg/m3 
Length 1200mm
Material Rock mineral wool ǀ Aluminium Foil
Pack Coverage 11.52m2
Pack Quantity 16
R-Value 0.85m2K/W
Thermal Conductivity 0.035W/mK
Thickness 30mm
Width 600mm
Fire Classification Euroclass A1
Vapour Resistivity 5.00MNs/g.m.
Slab Coverage 0.72m2
Fire Reaction Non-combustible
Building Regulations Class ‘0’ 
Coverage 11.52m2
Finish Plain ǀ Foil faced
Quantity 16
Shipping method Articulated Vehicle ǀ Courier
Applications Floor ǀ Wall ǀ Roof ǀ Partitions
Foil faced One side
ECOSE Technology Yes
ETA Notification Yes
Features Foil backed slab ǀ Fire performance
Manufacturer Knauf Rocksilk®

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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.
30mm FOIL FACED RS45 Knauf Rock Mineral Wool Building Slab - 45kg density
30mm Foil Faced RS45 Rocksilk Knauf Insulation Slab 45kg ǀ pack of 16
£ 442.92