Fastener reference

• Concrete/solid brick

  Wedge anchor, chemical anchor for heavy; nail-in anchors only for light rails.

• Hollow brick/aerated

  Chemical anchor + mesh sleeve or special GB dowel; a standard dowel holds little.

• Drywall

  Molly/Driva anchors to 25kg; heavy — only into the stud through the drywall.

• Wood

  Wood screw with pilot hole; confirmat — for chipboard, euro screw — for solid.

A dowel's rated load assumes an ideal substrate: real capacity in aerated concrete is 5x lower. Rule: heavy on drywall → into the stud, on hollow → chemical, on concrete → anchor.