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View Product Reviews100mm Rockwool RWA45 Acoustic Sound Insulation Slab (2.88m2/Pack)
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Multi-application stone wool slab with strong acoustic, thermal, and fire performance. Suitable for walls, floors, and roofs. Most popular thickness, 100mm provides excellent sound reduction for stud walls and floor joists.
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Thu 25 Sep
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Product Overview
Multi-application stone wool slab with strong acoustic, thermal, and fire performance. Suitable for walls, floors, and roofs. Most popular thickness, 100mm provides excellent sound reduction for stud walls and floor joists.
Delivery & Returns Information
How Our Delivery Works
We work with a nationwide network of trusted suppliers. As a result, items in your basket may be supplied by different suppliers and delivered separately. Where this applies, you'll see multiple delivery charges at checkout. We always aim to group products from the same supplier to keep delivery costs as low as possible.
Delivery Areas & Charges
Delivery charges listed on our website apply to mainland UK, excluding the following postcode areas: AB, CF, DD, DG, FK, KW, IV, LA, LD, LL, NP, PA, PH, SA, SY
If your delivery address falls within one of these postcode areas, we’ll be in touch before processing your order to confirm any additional delivery costs.
Please note: We do not currently offer delivery outside the UK mainland.
Standard (Nationwide) Delivery
| Insulation, Plasterboard and Drylining Products | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £350 | £35 ex. VAT |
| Over £350 ex. VAT | FREE |
| Timber & Sheet, Building Materials, Joinery and Gardens & Landscaping Products | |
| ORDER VALUE | DELIVERY CHARGE |
| Under £100 | £15 ex. VAT |
| Between £100 - £300 ex. VAT | £10 ex. VAT |
| Over £300 ex. VAT | FREE |
| Screws & Fixings and Adhesives & Sealants | |
| ORDER VALUE | DELIVERY CHARGE |
| Under £50 | £5 ex. VAT |
| Over £50 ex. VAT | FREE |
Express Delivery
| Express Delivery - Insulation and Plasterboard & Drylining | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £400 | £50 ex. VAT |
| Over £400 ex. VAT | £35 ex. VAT |
| Express Delivery - Timber & Sheet, Building Materials, Joinery and Gardens & Landscaping Products | |
| ORDER VALUE | DELIVERY CHARGE |
| Under £300 | £50 ex. VAT |
| Over £300 ex. VAT | £35 ex. VAT |
Returns
We offer a 30 day returns policy on any faulty products.
Key Features
- {{home}} Use in ceilings, walls and floors
- {{local_fire_department}} A1 non-combustible
- {{density_medium}} 45kg/m3 density
- {{volume_off}} Excellent acoustic and thermal performance
- {{build}} 600mm width to fit between studwork
- {{public}} Zero Ozone Depletion Potential (ODP)
Technical Specification
| Product: | RWA45 |
|---|---|
| Material Type: | Rock Mineral |
| Thickness: | 100mm |
| Width: | 600mm |
| Length: | 1200mm |
| Pieces Per Pack: | 4 |
| Sales Unit: | Pack |
| Sales Unit Coverage: | 2.88m2 |
| Brand: | Rockwool |
| Manufacturer's Reference: | 209274 |
| Thermal Conductivity: | 0.035W/mK |
| Density: | 45kg/m3 |
| Fire Rating: | A1 Non-Combustible |
Technical Downloads
Product Overview
Stone wool insulation slab, measuring 100mm in thickness, designed for use in internal partitions, floors, and roof applications.
Manufactured from high-density stone wool, the slab combines excellent acoustic absorption with reliable thermal insulation and inherent fire resistance.
Its rigid composition allows a close friction fit between studs or joists, preventing gaps that could compromise performance.
Non-combustible and classified as Euroclass A1, the slab contributes to improved fire safety within the building fabric. Its fibre structure also provides effective sound reduction, limiting noise transfer between rooms and floors.
At 100mm thick, this slab is the most widely specified option in the RWA45 range.
It is particularly suited to stud walls and intermediate floors, where its depth provides robust sound insulation alongside strong thermal and fire performance.
Features & Benefits
- Euroclass A1 fire classification: Non-combustible in accordance with BS EN 13501-1.
- Stone wool mineral slab: Naturally resistant to rot, fungal decay, and insect attack.
- Square-cut edges: Butt together cleanly for continuous insulation layers.
- Porous fibre structure: Absorbs sound energy, reducing noise transfer through walls and floors.
- Semi-rigid slab: Simple to shape with a knife and friction-fit between studs or joists.
- Thermal conductivity 0.035 W/m·K: Helps maintain building energy efficiency.
- Sustainable manufacture: Made from natural volcanic rock, recyclable, zero ODP/GWP.
- 100mm thickness: Delivers maximum thermal and acoustic performance in the RWA45 range.
Applications
- Stud partitions with maximum acoustic demand: Provides the highest level of airborne sound reduction.
- Intermediate floors with deep joists: Delivers top performance for separating floors.
- Ceilings beneath noisy spaces: Best solution for reducing sound transfer.
- Drylined partitions and linings: Maximises fire, thermal, and acoustic ratings.
Installation Guidance
- Cut accurately with knife or insulation saw: Ensures a close friction fit.
- Fit slabs snugly with no gaps: Maintains fire and acoustic integrity.
- Wear gloves and protective clothing: Prevents irritation from mineral fibres.
Compliance & Performance
- Thermal conductivity: Declared 0.035 W/m·K (EN 13162).
- Fire performance: Euroclass A1 non-combustible (BS EN 13501-1).
- Certification: CE and Key marked to BS EN 13162:2012 + A1:2015.
- Acoustic standards: Supports compliance with Approved Document E (England & Wales), Section 5 (Scotland), and BB93 (schools).
- Marine/offshore certification: Lloyd’s Register approved as non-combustible.
Customer 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.
Easy to use
Great insulation as part of a soundproofing solution
Arrived on time, thank you
received as expected, thanks
We used this in our extension and it's really helped with soundproofing
Arrived on time and did the job
Great product
Really helped to reduce noise between floors
Perfect for my new home gym!
Easy to install, just needed a sharp knife to cut the slabs to size for my wall
Great product, I bought this for the acoustic performance and it was the ideal solution to soundproof my home gym
Ordered and received to my delivery postcode in 2 days
Completely changed the noise from the hallow stairs between bedrooms. Would buy again.
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.
grand
Excellent product and service, thank you
good at making it quiet
very good
really worked well in my flat
Great at reducing sound
amazing slab
Really impressed with the sound reduction
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