Insulate external full-fill masonry cavity walls with Knauf Insulation DriTherm Cavity Slab 32, supplied in a 1200 x 455 x 150mm size. This high-performance glass mineral wool slab offers a thermal conductivity of 0.032 W/m.K, delivering low heat transmission for energy-efficient wall constructions.

Manufactured with a water-repellent additive to resist moisture ingress, the slab is engineered to adapt to slight imperfections in the substrate and knit together at joints. This eliminates air gaps and preserves thermal performance for the lifetime of the building. The slab friction-fits securely between wall ties without needing ancillary products such as retaining discs or jointing tape, providing a full-fill solution that does not require cavity barriers.

DriTherm Cavity Slab 32 holds a BBA Agrément certificate for use in all exposure zones, including very severe environmental areas. Non-combustible with a Euroclass A1 fire rating, it holds a CCPI Verification Mark and is manufactured using Knauf Insulation's unique bio-based binder, ECOSE Technology.

• 1200 x 455 x 150mm slab – sized to friction-fit between standard wall ties easily
• 0.032 W/m.K thermal conductivity – delivers low thermal transmission for cavity walls
• Water-repellent additive – resists moisture ingress across all exposure zones
• Knits together at joints – adapts to substrate imperfections to eliminate thermal air gaps
• No ancillary fixings needed – friction-fits without retaining discs, tapes, or cavity barriers
• Euroclass A1 non-combustible – ensures maximum fire safety with ECOSE Technology binder
• BBA certified and CCPI verified – approved for use in severe exposure zones

Delivery & Returns

Delivery: This item is delivered to the kerbside or the nearest accessible road point at your property. The driver won't be able to bring it into your property, so please make sure you can move it from there.

Due to courier restrictions, we're unable to deliver this item to the following postcodes:
Scotland: AB10–16, AB21–25, AB30–39, AB41–45, AB51–56, IV1–28, IV30–32, IV36, IV40–56, IV63, KW1–17, PA1–20, PA21–38, PA41–49, PA60–78, PA80, PH1–26, PH30–44, PH49–50
Wales: LD1–8, LL21–49, LL51–78, SA1–20, SA31–48, SA61–73, SY15–25

Returns: As this is a bulky item, unwanted returns incur a £40 collection fee (replacing our standard £9 fee). There is no charge for items that are faulty, damaged or sent in error. To arrange a collection, please contact our Customer Services team.

This item will be delivered directly by our supplier. Lead times are shown on the product and trolley pages and are always advertised in working days (Monday to Friday).

• If your order contains items stocked by us and items that come direct from the supplier, your order will be automatically split and processed accordingly.
• We will pass the details you give us, including delivery details, your email address and your phone number, to the relevant supplier.
• Most of our suppliers can deliver to any UK address. Delivery to remote or offshore postcodes may take a little longer than the advertised lead time. If the supplier cannot deliver to your postcode or we believe your order may take longer, we will try to tell you beforehand.
• Items that come direct from a supplier will be delivered by the courier chosen by the supplier. Where possible, suppliers will update you with delivery information. This may be by email, phone call or text message.
• Items delivered direct from suppliers cannot be returned through a store. You would need to return these items direct to the supplier, unused and in their original packaging, at your expense. You can arrange for most items to be collected by contacting our Customer Services team. A fee of £9* will be taken off your refund. There is no charge for faulty items being collected. *For big and bulky items, additional charges may apply.
• Please note, you cannot return bespoke or made-to-measure items unless they are faulty.