SKU: 88780499187

Knauf Dritherm Cavity Slab 37 125mm x 1200mm x 455mm

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Description

Knauf Dritherm Cavity Slab 37 125mm x 1200mm x 455mmDriTherm Cavity Slabs are semi rigid or rigid slabs of non combustible, water repellent, glass mineral wool. They are 455mm wide to suit standard vertical wall tie spacings, ensuring a closed joint with adjacent slabs. Performance THERMAL DriTherm Cavity Slabs have thermal conductivities ranging from 0. 032 to 0. 037 W mK. FIRE DriTherm Cavity Slabs are classified as Euroclass A1 to BS EN 13501 1. Benefits British Board of Agrment approved for use in

DriTherm Cavity Slabs are semi-rigid or rigid slabs of non-combustible, water repellent, glass mineral wool. They are 455mm wide to suit standard vertical wall tie spacings, ensuring a closed joint with adjacent slabs.

Performance

THERMAL

DriTherm Cavity Slabs have thermal conductivities ranging from 0.032 to 0.037 W/mK.

FIRE

DriTherm Cavity Slabs are classified as Euroclass A1 to BS EN 13501-1.

Benefits

    • British Board of Agrément approved for use in all exposure zones
    • Excellent thermal and fire performance
    • Water repellent
    • Slabs ‘knit’ together, thus eliminating air gaps between adjacent slabs



Application

DriTherm Cavity Slabs are for the thermal insulation of masonry cavity external walls and are installed to fully fill the cavity. They are approved for use in buildings up to 12m high in any exposure zone and for use in multi-storey applications up to 25m in height

Environmental

DriTherm Cavity Slabs represent no known threat to the environment and have zero Ozone Depletion Potential and zero Global Warming Potential.

Knauf Insulation mineral wool products with ECOSE Technology benefit from a revolutionary, bio-based, formaldehyde-free binder technology, based on rapidly renewable materials, instead of petro-based chemicals. It reduces embodied energy and delivers superior environmental sustainability.

The technology has been developed for Knauf Insulation’s glass and rock mineral wool products, enhancing their environmental credentials without affecting the thermal, acoustic or fire performance. Insulation products made with ECOSE Technology contain no dye or artificial colours – the colour is completely natural.

Additional

Standards

DriTherm Cavity Slabs are manufactured in accordance with BS EN 13162, EN 16001 Energy Management Systems, OHSAS 18001 Occupational Health and Safety Management Systems, ISO 14001 Environmental Management Systems, and ISO 9001 Quality Management Systems, as certified by Bureau Veritas.

Durability

DriTherm Cavity Slabs are odourless, rot proof, non-hygroscopic, do not sustain vermin and will not encourage the growth of fungi, mould or bacteria.

Moisture resistance

Tests by the British Board of Agrément confirm that DriTherm Cavity Slabs will not transmit water to the inner leaf. Nor will they transmit moisture by capillary action across the cavity or from below damp proof course level.

Vapour resistivity

DriTherm Cavity Slabs offer negligible resistance to the passage of water vapour and have a water vapour resistivity of 5.00MNs/g.m.

Guarantee

DriTherm Cavity Slabs are guaranteed* for 50 years to resist the transmission of liquid water from the outer masonry leaf to the inner masonry leaf in new cavity walls and to have a thermal conductivity of 0.032 to 0.037 W/mK at normal building temperatures

*Available by application to Knauf Insulation Ltd

Certification

DriTherm Cavity Slabs are certified by British Board of Agrément Certificate 95/3212. Approval can be sought from Knauf Insulation Ltd and the British Board of Agrément for DriTherm Cavity Slab’s use in buildings over 25m high.

Handling and storage

DriTherm Cavity Slabs are easy to handle and install, being lightweight and easily cut to size, where necessary. They are supplied in polythene packs which are designed for short term protection only. For longer term protection on site, the product should either be stored indoors, or under cover and off the ground. DriTherm Cavity Slabs should not be left permanently exposed to the elements.

    • Thermal conductivity (W/mK): 0.035
    • Thermal resistance (m2K/W): 1.40
    • Length (mm): 1200
    • Width (mm): 455
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
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Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 88780499187

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A
Verified Purchase
Andy
Battle Creek, US
★★★★★ 5
Made a big improvement in cabin noise—highly recommend
Model: SLH20025
Siless Hybrid made a huge difference in reducing noise in the floor of my truck cabin. In some areas, there was basically just bare sheet metal between the inside and outside, so adding this really helped the truck feel more solid and noticeably quieter on the road. I used Kilmat on the doors, and honestly I wish I had used Siless Hybrid there too, but it was too late by the time I realized the difference. This material is very sticky, easy to cut, and simple to apply, which made the install pretty smooth. Just a heads-up: the tacky side gets messy and will bond to clothing really easily, so be careful during installation. Overall, I’d definitely buy it again—great product with real results.
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Reviewed in the United States on December 2, 2025
A
Verified Purchase
AmazinFrank
West Palm Beach, US
★★★★★ 5
Very good product at a fair price
Model: SLH20025
Very good sound deadener and heat shield, it is a bit sticky to work with, but easy to shape and cut
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 19, 2026
E
Verified Purchase
Eric Caldeira
Lake Worth, US
★★★★★ 5
I wish I had Siless 20 years ago!!!
Model: SLH20025, Model: SLH20025
I have installed all kinds of insulation in vehicles over many years. I only needed to purchase 2 boxes to complete the entire interior siding of my 2025 chevy express, what a great value! I wanted to insulate my locksmith van for sound and heat. The sound reduction virtually eliminated the road noise. These panels also look amazing. It got up to 110F in the sun with the doors closed. After adding Siless insulation the temperature maxed out at 97F. That is a massive difference. Plus, I didn't even finish with the roof before testing. Siless Hybrid 3in1 was extremely easy to cut and adhere onto metal panels. I'm impressed with the quality of the individual panels and the adhesive is not toxic smelling compared to some others. My favorite thing about these panels is you can actually take them off and readjust them before they finally stick and they do not leave any black residue behind when you pull them up to adjust them. All I needed was a heat gun, knife and a roller to complete this job. The size of each panel is perfect, you can handle them with ease. I probably won't need your product again for a while, but when I do I will definitely be back.
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Reviewed in the United States on September 21, 2025
M
Verified Purchase
Mark Kadrich
Battle Creek, US
★★★★★ 5
Works well and is easy to install.
Model: SLH20025, Model: SLH20025
I was sound and heat insulating a generator bay in my class A RV so I did three tests before and during material application: I did a sound level test to see how effective the material was for my application, a "stickiness" test, and a flammability test. This was indoors on a dry 78°F day. From beginning to end, the entire process, including testing, took 5 hours to install 25 sqft or material in a very complex area. One hour for cleaning, 3 hours for installation, and 1 hour for test setup and testing. Using a sound meter, I took before and after readings and determined that I reduced the sound level by 2.2 db (40% energy decrease) with a noticeable decrease in sound and frequency. The generator bay is located under the master bedroom in the aft portion of the coach. The sound went from a rattling, vibrating generator noise to a more tolerable low level rumble. The material was easy to apply. I did some testing prior to application and determined that surface preparation is key. I cleaned my painted metal surface and then degreased with acetone and the material stuck well. Be careful and purposeful when you apply the material because once it was stuck to the metal, it was quite difficult to remove or reposition. Since it was going to be installed into a gasoline powered generator bay located under our sleeping quarters, I did some flame testing to determine the level of risk. Although not highly flammable after installation, my testing revealed that the PE used will catch on fire under certain circumstances. In order to reduce the risk, I used aluminized duct tape to ensure that all the edges were sealed and the PE was not exposed to direct flame in the event of a fire. I also decided to install an automatic fire extinguisher as an added precaution. In all fairness there should be one installed in the generator bay anyway. All in all, I am very satisfied with the product and the results. I have recommended this product to my other RV owner friends.
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Reviewed in the United States on April 13, 2025
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Verified Purchase
Josh
Chelsea, US
★★★★★ 5
Great product. Best value i could find
Model: SLH20025
I'm using talk to text, so forgive any grammatical and spelling errors. I ordered this product after doing a bit of research on sound dampening materials. I had been doing car stereo for quite some time since my teens. Itook a break for 20 years or so. I'm now 40 and back in the day there was dynamat. And that was about it. as irecently bought a new 2017 F350 crew cab. I wanted to put in a new stereo system and being that it was my dream truck. I was going to put in my dream stereo. But before I could do that, I needed to start with the sound deadening. I looked into today's leading product and found a company called resonx. Had taken their place as king of the hill in sound deadly. I researched their products and found the materials they were built from and Silas was the closest match at the best price I used Silas Max. First, then Silas 3 and 1 hybrid over that on all exterior panels. Then, on the interior panels. I used the 3 and 1 hybrid . on the floor I used Silas Max. Then, the 3 and 1 hybrid, then Silas liner over that the car is incredibly quiet . As far as sound dampening and deadening, it works very well for the money really can't beat it. Do your homework no How and where to apply it? And you really can't go wrong or about $400. I did. What would have cost me easily? Two thousand in other brands highly recommend the product prep work.Is everything do your homework?Do it right and you will be happy with this stuff
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Reviewed in the United States on May 6, 2026

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