Rockwool Flexi

Rockwool

Description

Acoustic and thermal flexi edge building slabs

Dual purpose acoustic and thermal mineral wool insulation with a patented Flexi® edge along one side.

Suitable for a wide range of applications, fitting all stud and joist centres with ease.

Will not slump, even if studs shrink.

Non-combustible – Euroclass A1.

Made from diabase rock, which is a renewable and plentiful natural resource.

Does not contain gases that have ozone depletion potential (ODP) or global warming potential (GWP).

Thicknesses and Availability:

This Rockwool Range includes the following readily available product thicknesses: 50mm, 60mm, 70mm, 90mm, 100mm, 140mm, and 180mm (some thicknesses may only be available in pallet quantities as they will need to be sourced from the manufacturer before being delivered to site).

The following thicknesses are manufactured to order and have minimum order requirements: 120mm (minimum order: 16 x pallets).

Product options

Quantity Product ex-VAT inc-VAT  
£644.48 £773.38
£40.28 £48.34
£797.93 £957.52
£39.90 £47.88
£596.91 £716.29
£37.31 £44.77

Availability Indicators

Rockwool Flexi is sent out from depots nationwide and is subject to the Local Depot Delivery minimum order levels and delivery charge thresholds.

Reasonable stock levels of popular thicknesses are held at larger depots. Please allow extended lead times where products need ot be sourced from the manufacturer before being delivered to site.

Rockwool reserves the right to change stocked products - while we will do all we can to keep on top of changes, availability and lead times my vary.


  • Generally 1 to 3 working days for delivery
  • Generally 1 to 5 working days for delivery
  • Generally 5 to 10 working days for delivery
  • Special request or made to order item, allow extended lead times. Minimum order levels may apply.
  • Please call to check availability and approximate lead times

Delivery charges will be calculated at check-out. Please visit our Ordering From Us page for further details on minimum order levels and delivery charges. If you have any queries, please do not hesitate to contact me via our Contact Form or on 01903 899 898.

Product Application

Thermal and Acoustic flexi edge Building Slab

Rockwools versatile flexi edge building slab, Rockwool Flexi, is suitable for use in pitched roof rafters, framed external walls, internal partitions, intermediate floors, separating walls and floors, and timber suspended ground floors.

Product Make-up

Core: Durable non-combustable stone wool spun from volcanic rock, resin bonded into slabs with a unique flexible edge (approx. 50mm compression) along one side.

Product Properties

Thickness 50mm to 140mm  
Slab Length 1.2m  
Slab Width 0.4m and 0.6m  
Slab Edge Square  

Product Performance

Thermal Conductivity 0.038 - 0.035 W/mK  
Fire Performance Classification A1 BS EN 13501-1
Surface Spread of Flame Non-combustable  
Nominal Density approx. 33 kg/m³  
Vapour Resistance Negligable  

Product Variants

Product Thickness Thermal Resistance kg/m²
Flexi 50mm 50mm 1.32 m²K/W 1.65 kg/m²
Flexi 60mm 60mm 1.58 m²K/W 1.98 kg/m²
Flexi 70mm 70mm 1.84 m²K/W 2.31 kg/m²
Flexi 90mm 90mm 2.37 m²K/W 2.97 kg/m²
Flexi 100mm 100mm 2.63 m²K/W 3.30 kg/m²
Flexi 120mm 120mm 3.16 m²K/W 3.96 kg/m²
Flexi 140mm 140mm 4.00 m²K/W 4.62 kg/m²