140mm Rockwool Flexi Insulation Slab

140mm Rockwool Flexi is a high-performance stone wool insulation engineered to deliver both thermal and acoustic performance in a single product. Distinguished by its patented flexible edge design, this material provides superior installation characteristics.

The 140mm Rockwool Flexi slab features a patented flexible edge that creates a friction fit against timber framing and structural supports. Installation is straightforward—simply position between fresh timber studs. As timber naturally shrinks during the drying process, the insulation expands to maintain contact and eliminate gaps. Classified as Euroclass A1 non-combustible, 140mm Flexi Slab delivers enhanced fire safety alongside thermal and acoustic insulation capabilities.

This product performs effectively across multiple building applications, including pitched roof installations, timber-framed external walls, and internal partition systems.

Product Specification

Thickness: 140mm

Width: 400mm

Length: 1200mm

Dimensions: 1200x400mm - 1.92m2

Density: 33kg/m3

Weight of 1m2: 2.63kg

Weight: 8.87kg

Thermal Conductivity: 50-120mm 0.038 W/mK / 140mm> 0.035 W/mK

R-Value: 4m2K/W

Product Standards: BS EN 13162

Reaction to fire (Euroclass): Euroclass A1

Acoustic: Achieves Part E (resistance to sound) when installed in accordance to ROCKWOOL guidelines

Water vapour resistance: 5.2 MNs/gm

Water repellent: Yes

FEATURES AND BENEFITS:

• Excellent thermal performance. • Effective noise absorption. • Euroclass A1 non-combustible. • FLEXI Edge ensures tight friction fit. • Remains securely in place when timber studs dry out and contract. • Mineral wool insulation batts (slabs) CE marked to BS EN 13162:2012+A1:2015

Applications

1. Intermediate Floor Insulation
2. Separating Floor
3. Rafter Line
4. Separating Wall
5. Partition Wall
6. Pitched Roof
7. Timber Frame
8. Floor Solutions

About

140mm Rockwool Flexi Non-combustible multi-use insulation slab represents an innovative solution featuring a proprietary flexible edge technology. This patented design enables rapid, friction-fit installation with minimal effort, guaranteeing consistent performance across all applications. The flexible edge maintains optimal contact between the product and supporting structure, streamlining the installation process and maximising thermal efficiency.

Rockwool Flexi 140mm demonstrates exceptional versatility across diverse building scenarios. From timber-framed external walls and roof rafters to floor systems and partition walls, this material performs reliably in all contexts. Its adaptability ensures seamless integration throughout building envelopes, contributing to measurable improvements in both thermal and acoustic performance.

With 140mm Flexi Insulation Slab, you gain access to innovative technology and proven quality engineered to satisfy demanding insulation requirements with confidence and ease.

Info

Browse our comprehensive Rockwool range and refine by thickness or coverage area using the left-hand filters. For technical advice on product suitability for your specific project, or to request a quantity discount quotation, contact us by phone on +4402038839057, email sales@insulationbee, or use our Live Chat service - Lowest UK Insulation Prices.