Dübel

Dübel are mechanical anchors used to create secure mounting points in materials that cannot reliably hold a screw by itself, such as masonry, brick, concrete, or hollow walls. They transform the screw into an expansion or clamping mechanism that transfers load from the fastener to the surrounding substrate.

During installation, a predrilled hole is prepared to match the Dübel size. The Dübel is inserted and the screw is driven in; as the screw tightens, the Dübel expands, deforms, or engages its internal ribs, creating friction and a stable grip. This allows a screw to bear loads such as shelves, mirrors, or fixtures.

Dübel come in several form factors. Plastic expansion dowels (Spreizdübel) are common for masonry and concrete. Metal expansion anchors provide higher load capacities. Hohlraumdübel (hollow-wall anchors) are designed for hollow or plasterboard walls, while Gipskartondübel are specialized for gypsum boards. There are also chemical or adhesive anchors for high-load applications, which use resin to bond the fastener to the substrate.

Choosing the right Dübel depends on material (solid masonry, concrete, brick, gypsum board), load type and magnitude, screw diameter, and whether the wall is solid or hollow. Correct hole size and installation depth are essential. In outdoor or damp environments, corrosion resistance matters, with stainless steel variants available. For very heavy or dynamic loads, adhesive or mechanical anchors may be preferred over basic plastic dowels.