Top Duo warm roof deck insulation fixings a dual thread roofing screw. For fastening insulation on roofs with thicknesses up to 300mm with a dual thread to eliminate compression of the insulation.
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Corrosion protection
blue+ is an innovative coating system with greater corrosion resistance than conventional electrogalvanised surfaces. In the blue+ system, a sealant is applied to a galvanised surface and reacts with it. In this way, any weak points in the galvanisation are safely sealed and protected. The coating is free of chromium(VI) oxide, which is classified among other things as being hazardous to the environment. Surfaces treated with blue+ have excellent resistance to mechanical stress.
Advantages blue+ coating
• Greater corrosion resistance than conventional galvanisation
• Can be used in usage classes 1 and 2
• Free of chromium(VI) oxide
• Resistant to mechanical stress
The Topduo double-threaded screw allows secure fastening of over-rafter insulation with both pressure-resistant and non-pressure-resistant insulating materials. Of course, the high extraction resistance in both connecting timbers also makes the Topduo attractive for many other applications in the field of timber-frame construction.
Advantages Topduo Roofing screw
• Double-threaded screw with new blue+ coating.
• Greater corrosion resistance than conventional galvanisation.
Can also be used for many other applications in timber-frame construction thanks to its high extraction resistance.