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100mm Rockwool RWA45 Acoustic Sound Insulation Slab (2.88m2/Pack)

URN: 3002254 In Stock
£22.69ex. VAT £7.88 per m2
£22.69ex. VAT
£7.88 per m2
100mm Rockwool RWA45 is a multi-application thermal, acoustic and fire insulation slab. This mineral wool insulation solution is purposed to minimise noise in a vast range of general building projects.

Nationwide Delivery

Wed 21 Jun

Product Overview

100mm Rockwool RWA45 is a multi-application thermal, acoustic and fire insulation slab. This mineral wool insulation solution is purposed to minimise noise in a vast range of general building projects.

100mm Rockwool RWA45 Acoustic Sound Insulation Slab (2.88m2/Pack)

URN: 3002254
£22.69ex. VAT

Delivery & Returns Information

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Standard (Nationwide) Delivery

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Over £300 ex. VAT FREE
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Under £100 ex. VAT £7.50 ex. VAT
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Express Delivery

Under £300 ex. VAT £75 ex. VAT
Over £300 ex. VAT £50 ex. VAT

This charge is based on delivery to mainland UK excluding the Scottish Highlands. If your delivery address is in the Scottish Highlands a member of our customer service team will contact you prior to processing your order should an additional delivery charge apply. We do not offer deliveries outside the UK mainland.

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We offer a 30 day returns policy on any faulty products.

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Key Features

  • Use in ceilings, walls and floors
  • A1 non-combustible
  • 45kg/m3 density
  • Excellent thermal and acoustic performance
  • 600mm width to fit between studwork
  • Zero Ozone Depletion Potential (ODP)

Technical Specification

Technical Specification
Material Type:Rock Mineral
Pieces Per Pack:4
Sales Unit:Pack
Sales Unit Coverage:2.88m2
Manufacturer's Reference:209274
Thermal Conductivity:0.035W/mK
Fire Rating:A1 Non-Combustible

Hear the difference with 100mm Rockwool RWA45 Acoustic Insulation Slab: a robust 3-in-1 thermal, acoustic and fire insulant. This multi-application mineral wool insulation solution is suitable for a host of general building projects and specialist specifications- from residential extensions to refurbishment builds in both commercial and leisure applications. 

Thanks to its non-directional fibre structure and 45kg/m3 density, 100mm RWA45 is second to none when it comes to acoustic performance, making it the ideal solution for use in separating floors and internal walls. In terms of its fire performance, 100mm Rockwool RWA45 slab remains unbeatable, achieving an A1 non-combustible rating - the highest possible level of fire resistance. 

Users of RWA45 can rest assured that these premium-quality semi-rigid slabs are not only optimising the fire protection of their build but (with a thermal conductivity of 0.035 W/mK) are also working in tandem to protect its thermal envelope.

Rockwool Sound Insulation Slab Applications

Unrivalled in its acoustic performance, 100m RWA45 (often referred to as a Sound Slab - no prizes for guessing why), makes for the ideal solution when soundproofing separating floors and internal walls. Not only will it maintain the volume within your project, but it will also protect it with an immaculate A1 non-combustible rating. 

To make life easier, Rockwool slabs are resin bonded and cut to 1200mm x 600mm, which allows them to slot perfectly between standard stud partitions and floor joists that are at 600mm centres. 

The slabs can be used in multiple applications, including the following:

  • Interior timber or steel partition walls
  • Interior timber frame floors
  • Interior timber frame ceilings
  • Acoustic ceilings and partition panels
  • I-joist interior partitions
  • Pitched roofs
  • Party walls
  • Industrial applications

Rockwool 100mm RWA45 Specifications

With thermal, acoustic, fire prevention and water repellent properties on offer, Rockwool 100mm RWA45 has you covered in a wide range of areas.

 Let's have a look at the specs:

  • Zero Ozone Depleting Potential (ODP) and Global Warming Potential (GWP)
  • Rot-resistant - withstands mould and mildew
  • Thermal conductivity of 0.035 W/mK
  • Fire Classification (Reaction To Fire) - Euroclass A1 (BS EN 13501-1) 
  • Hydrophobic - thanks to its water repellent properties
  • Excellent thermal, acoustic and fire insulation - robust insulation solution

Rockwool 100mm RWA45 Certifications

BS EN is British and European Standard Specifications. With over 100 years of experience, the British Standards Institute is recognised as the UK’s National standards body. BS EN considers Rockwool both:

  • A1 non-combustible in accordance with BS EN 13501-1 - achieving the highest possible level of fire performance/resists high temperatures
  • CE and Key marked in accordance with BS EN 13162:2012 + A1:2015.v

100mm Rockwool slabs are also certified by Lloyd's register of shipping as non-combustible materials for use on:

  • Fixed offshore installations
  • MED classed ships- DTLR MCA approval
  • Rated non-combustible in accordance with ISO 1182 and IMO A. 799

Rockwool RWA45 Insulation Storage & Handling

RWA45 slabs boast a soft, fibrous texture, very similar to a loaf of bread. Due to this soft composition, a simple serrated blade is all you will need to slice through them. 

When it comes to storage, we advise that you store the slabs inside, protected from the elements. 

100mm RWA45 Acoustic Performance

With a density of 45kg/m3, Rockwool thermal and acoustic insulation quells unwanted noise like no other. The non-directional fibre structure of the mineral wool essentially traps sound and keeps it locked in so it will not travel to the other side. 

It is this absorbent nature which renders 100mm RWA45 Slabs the most popular acoustic and soundproofing insulation product on the market. In comparison to other insulation materials, Rockwool offers excellent acoustic performance and is highly effective at preventing noise transmission from room to room as well as deadening sound vibrations. 

Due to the fact that noise tends to bleed most through internal and separating walls, RWA45 is best suited within these applications to keep noise levels to a comfort-friendly decibel. 

The RW Slab product range consists of a variety of thicknesses and densities.

About Rockwool Insulation

Rockwool is recognised as being the market-leading acoustic insulation solution. The Rockwool RW slab product range offers outstanding fire, acoustic and thermal insulation properties as well as lifelong durability. 

Rockwool RW semi-rigid slab products, either un-faced or with an aluminium foil or glass fleece on one or both surfaces, achieve an A1 classification in accordance with BS EN 13501-1 and thus meet the requirements of non-combustible materials, as defined in UK and Ireland Building Regulations.

The 100mm is the most popular thickness of the Rockwool RW slab range and has a pack quantity of 4 slabs (25mm, 50mm, 75mm, and 100mm) as well as a thermal conductivity of 0.035 W/mK.


5/5 based on 23 reviews

Fantastic product. When it came to adding these in between the studwork, they were simple to fit into place and then to cut I used a bread knife, as I didn't have a drywall knife - the slabs are like you are cutting bread! The RWA45 slabs have helped reduce noise between rooms since I've installed and I would recommend buying them.

Lenny Silverman on

Easy to use

Mo H on

Great insulation as part of a soundproofing solution

Graham Needs on

Arrived on time, thank you

Jill P on

received as expected, thanks

Grace Lint on

We used this in our extension and it's really helped with soundproofing

Ayla Kim on

Arrived on time and did the job

Grant S on

Great product

Ian K on

Really helped to reduce noise between floors

Chris Eldersbury on

Perfect for my new home gym!

Lily L on

Easy to install, just needed a sharp knife to cut the slabs to size for my wall

Alexi H on

Great product, I bought this for the acoustic performance and it was the ideal solution to soundproof my home gym

John Barrett on

Ordered and received to my delivery postcode in 2 days

Pete D on

Completely changed the noise from the hallow stairs between bedrooms. Would buy again.

Martin Chivers on

Great acoustic insulation slabs. Really reduced the sound from upstairs after my daughter moved back in. Next time I need any acoustic and thermal insulation, I'll be sure to come back to this site.

Daniel Silva on


Chris Thanet on

Excellent product and service, thank you

Lianne Bowden on

good at making it quiet

Ryan Edwards on

very good

Evan Cross on

really worked well in my flat

Oliver Smart on

Great at reducing sound

Samuel Folger on

amazing slab

Theo Cyproti on

Really impressed with the sound reduction

Stefan Bishopstort on

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