40mm Rockwool RWA45 Acoustic Sound Insulation Slab (8.64m2/Pack)
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| £33.52ex. VAT | £33.17ex. VAT | £32.15ex. VAT |
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Fri 12 Jun
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Key Features
- {{volume_off}} Excellent acoustic and thermal performance
- {{public}} Zero Ozone Depletion Potential (ODP)
Technical Specification
| URN: | 3002257 |
|---|---|
| Product: | RWA45 |
| Brand: | Rockwool |
| Application: | Ceilings, Walls, and Floors |
| Indoor/Outdoor Usage: | Indoor |
| Material Type: | Rock Mineral |
| Thickness: | 40mm |
| Width: | 600mm |
| Length: | 1200mm |
| Weight: | 15.55kg |
| Sales Unit: | Pack |
| Sales Unit Coverage: | 8.64m2 |
| Pieces Per Pack: | 12 |
| Fire Rating: | A1 Non-Combustible |
| Moisture Resistant: | Water repellent & Non-hygroscopic |
| Thermal Conductivity: | 0.035W/mK |
| Density: | 45kg/m3 |
| Certification: | BS EN 13162 |
| Edge: | Square |
| Manufacturer's Reference: | 181175 |
Technical Downloads
Product Overview
Stone wool insulation slab, measuring 40mm 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 40mm thick, the slab offers a balance between minimal wall build-up and meaningful acoustic performance.
It is often specified in partitions, linings, and ceiling systems where space is limited but higher sound absorption is required than thinner slabs can deliver.
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.
- 40mm thickness: Balanced choice for partitions needing acoustic insulation.
Applications
- Precision cutting: Use a sharp insulation saw or broad-bladed knife to cut slabs slightly oversized to ensure a compressed friction fit.
- Seamless abutment: Butt all joints tightly together with no visible gaps to maintain the continuity of the fire and acoustic barrier.
- Mechanical support: Secure with appropriate netting or insulation hangers when installing in overhead applications to prevent gravity-induced movement.
- Environmental protection: Store slabs undercover and off the ground to ensure the material remains dry and free from contaminants prior to installation.
- Personal protection: Wear loose-fitting clothing, gloves, and safety goggles to minimise skin and eye contact with mineral fibres.
Installation Guidance
- Precision cutting: Use a sharp insulation saw or broad-bladed knife to cut slabs slightly oversized to ensure a compressed friction fit.
- Seamless abutment: Butt all joints tightly together with no visible gaps to maintain the continuity of the fire and acoustic barrier.
- Mechanical support: Secure with appropriate netting or insulation hangers when installing in overhead applications to prevent gravity-induced movement.
- Environmental protection: Store slabs undercover and off the ground to ensure the material remains dry and free from contaminants prior to installation.
- Personal protection: Wear loose-fitting clothing, gloves, and safety goggles to minimise skin and eye contact with mineral fibres.
Soundproofing Guidance
- Mass Enhancement: Combine slabs with high-density soundproof plasterboard to significantly increase the total mass of the partition.
- Decoupling Strategy: Use resilient bars or independent stud frames in conjunction with the slabs to prevent mechanical vibration from traveling through the structure.
- Acoustic Sealing: Apply acoustic sealant to the perimeter of the partition and around any penetrations to prevent "flanking" noise from bypassing the insulation.
- Cavity Management: Ensure the slab fills at least 75% of the cavity depth to provide optimal sound absorption and prevent internal resonance.
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 Building Regulations Approved Document E (England & Wales), Section 5 (Scotland), and BB93 (schools) for acoustic performance in internal and separating walls/floors.
- Sound Absorption Class: Achieves Sound Absorption Class C (aw 0.60). Balances space-saving with effective mid-range frequency dampening.
- Marine/offshore certification: Lloyd’s Register approved as non-combustible.
Delivery & Returns Information
Delivery charges vary by product category and order value. Items may ship from different suppliers and arrive separately, so delivery charges can be shown per part of your order at checkout.
Standard (Nationwide) Delivery
| Insulation, Plasterboard and Drylining Products | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £400 | £45 ex. VAT |
| Over £400 ex. VAT | FREE |
Express Delivery
| Express Delivery - Insulation and Plasterboard & Drylining | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £400 | £90 ex. VAT |
| Over £400 ex. VAT | £55 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 |
How delivery works
We work with a nationwide network of trusted suppliers. Items in your basket may be supplied by different suppliers and delivered separately. Where this applies, you will see delivery charges shown at checkout for each part of your order. We always aim to group products from the same supplier to keep delivery costs as low as possible.
Delivery areas
Delivery charges apply to mainland UK, excluding: AB, CA, CF, DD, DG, EH, EX, FK, KA, KW, KY, IV, LA, LD, LL, ML, NP, PA, PH, PL, SA, SY, TR, TQ and TD.
If your address is in one of these areas, we will contact you before processing your order to confirm any additional costs. We do not currently offer delivery outside the UK mainland.
What to expect on delivery day
- Deliveries are typically kerbside.
- Please ensure someone is on-site to accept delivery. For heavier items, help with offloading may be required.
- Many building materials arrive on large vehicles. If access is restricted, a specialist vehicle such as a HIAB may be required and could incur an additional charge.
Why delivery can cost more than typical parcel delivery
Building materials often travel on larger vehicles and usually carry fewer drops per run than parcel networks. That is why delivery charges can be higher than standard e-commerce shipping.
Returns
Returns depend on what you have bought and whether there is anything wrong with it. For full details on eligibility, timeframes, and exclusions, please see our full policy.
