Expanded DDS-Z Range

Innovation supports UK’s higher soffit insulation standards

The new DDS-Z fastener range holds the key to installing much greater depths of soffit liners with the smallest embedment depth into concrete, to help architects and clients to dramatically improve the thermal, acoustic and fire insulation standards in their buildings.

This range of high quality self-tapping fasteners is designed specifically for the attachment of ceiling insulation and acoustic boards to concrete soffits where the goal is to bring un-insulated floor structures up to the thermal requirements of the latest Building Regulations and beyond. It is an increasingly popular trend amongst the designers, owners or managers of buildings that feature car parking below ground or at ground level with residential or commercial space above – hence the need for noise reduction measures.

Soffit liners have long been seen as an effective solution but the increasingly high standards now being sought here in the UK has given rise to the use of much greater depths of mineral fibre insulation. As this requires significantly longer fasteners to drive through the multiple layers of insulation and anchor effectively into the concrete substrate with a minimal embedment depth, EJOT UK has responded by expanding the DDS-Z range.

EJOT DDS-Z fasteners are steel screws featuring a duplex coating and self-tapping thread for reliable fastening. Suitable to accommodate the deepest layers of insulation, the fasteners are available in lengths of 275, 300, 325 and 350 mm but need only a 25mm embedment into the concrete. They complement the established DDS range which offers a soffit liner solution where a fixing of up to 250mm is required.

Designed for easy installation, DDS-Z fasteners are suitable for use in cracked and non-cracked concrete with a C1-C3 corrosion resistance classification.

Richard Bowhay, Sales Manager for Building Fasteners at EJOT UK said: “Insulating the soffit below a concrete floor has long been recognised as an effective way to transform the quality and safety of a building, particularly for living, working and educational spaces above car parking.

“But as architects and insulation manufacturers in the UK push the boundaries to seek ever higher performance standards, it is vitally important that the right fastening solutions are available to ensure client goals can be realistically met without making the installation process difficult or costly. That’s why the EJOT technical team developed the DDS-Z, a product that combines strength, reliability and ease of use, with the quality guarantee that all EJOT fastening systems offer.”

Technical Support: Talk to our team

As one of the leading manufacturers of fasteners for the construction sector, EJOT UK is ideally placed to advise on the correct fastening solution for any soffit insulation project. To contact our technical team for support...

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Installing a DDS-Z is easy...

Filmed on site, this video shows just how easy it is to install DDS-Z Fasteners to secure soffit insulation in place. 

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  • For a secure fastening of ceiling and acoustic boards
  • With German DIBt approval
  • Recommended substrate: Concrete​​​​​​​


  • For installation in cracked and non-cracked concrete
  • Steel screw with duplex coating and self-tapping thread for reliable fastening
  • Corrosion resistance classification C1-C3
  • Easy installation: drill, fasten, done
  • Minimal embedment depth
  • Coloured lacquering of the fastener heads
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