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View Product Reviews50mm Knauf DriTherm Cavity Wall Insulation Slab 37 (6.55m2/Pack)
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Glass mineral wool slab for full-fill masonry cavity walls. Thermal conductivity 0.035 W/mK delivers reliable insulation performance. 50mm thickness suits narrow cavities in refurbishment projects.
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Product Overview
Glass mineral wool slab for full-fill masonry cavity walls. Thermal conductivity 0.035 W/mK delivers reliable insulation performance. 50mm thickness suits narrow cavities in refurbishment projects.
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 £300 | £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 external masonry cavity walls
- {{local_fire_department}} A1 non-combustible
- {{thermostat}} 0.035 W/mK thermal conductivity
- {{water_drop}} Water repellent
- {{public}} Zero Global Warming Potential (GWP)
- {{verified_user}} BBA certified
Technical Specification
| Product: | DriTherm 37 |
|---|---|
| Material Type: | Glass Mineral |
| Thickness: | 50mm |
| Width: | 455mm |
| Length: | 1200mm |
| Pieces Per Pack: | 12 |
| Sales Unit: | Pack |
| Sales Unit Coverage: | 6.55m2 |
| Brand: | Knauf Insulation |
| Manufacturer's Reference: | 316650 |
| Thermal Conductivity: | 0.037W/mK |
| Fire Rating: | A1 Non-Combustible |
Technical Downloads
Product Overview
Full-fill glass mineral wool insulation slab, measuring 50mm in thickness, for use in masonry cavity walls.
Produced with a high recycled glass content and ECOSE® Technology, it delivers strong thermal insulation while allowing vapour to pass through, supporting a healthier building fabric.
A thermal conductivity of 0.035 W/mK ensures effective energy efficiency, reducing heat loss and supporting compliance with modern Building Regulations.
With a Euroclass A1 non-combustible rating and full BBA certification for every UK exposure zone, it also delivers confidence in fire protection, durability, and performance over time.
At 50mm thick, the slab is suited to narrow cavity widths often found in older properties and refurbishment projects, offering a practical insulation solution where space is restricted while still delivering reliable thermal and acoustic performance.
Features & Benefits
- Non-combustible Euroclass A1 fire rating: Ensures maximum fire safety in external walls.
- Thermal conductivity 0.035 W/mK: Reliable thermal efficiency for narrow cavities.
- Water-repellent additive: Stops moisture transfer while staying vapour permeable.
- 455mm width: Fits standard wall tie spacing for a close jointed finish.
- Slabs knit together: Prevents air gaps and reduces thermal bridging.
- Lightweight and cuttable: Simple handling and fitting on site.
- ECOSE® Technology binder: No added formaldehyde and reduced embodied energy.
- 50mm thickness: Ensures that restricted cavities are fully filled, stopping draughts and heat loss while maintaining breathability.
Applications
- Narrow cavity walls (50mm): Designed for older housing and properties built with very slim cavity widths.
- Refurbishment and retrofits: Practical solution for upgrading insulation where cavity depth is restricted.
- Masonry cavity external walls: Provides long-term performance in narrow external wall constructions.
- Space-limited projects: Suitable for situations where maintaining a thinner wall build-up is essential.
Installation Guidance
- Cut to fit: Slabs can be trimmed cleanly with a sharp knife for an accurate fit.
- Close-butt joints: Ensure slabs are tightly butted together with no gaps to maintain insulation performance.
- Keep dry before fitting: Store indoors or under cover to protect the slabs until installation.
Compliance & Performance
- Euroclass A1 to BS EN 13501-1: Highest level of non-combustibility.
- BBA certified for all exposure zones: Approved for UK use in severe weather locations.
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