STAINLESS STEEL HEXAGON HEAD BI-METAL MULTIFIX MASONRY SCREWS

Hexagon Head Bi-Metal Multifix Masonry Screws — Fixing into masonry or concrete usually means installing a separate plug before the screw goes in, but a Multifix screw skips that step entirely - its aggressive thread form cuts its own mating thread directly into the wall of a pre-drilled hole as it's driven, so no plug is needed at all, provided the substrate is solid enough to hold a cut thread reliably. That makes it faster to install than a plug-and-screw system wherever the masonry or concrete is dense and consistent enough for direct thread-cutting to work, which is why it's typically specified for fixing frames, rails, brackets, and cladding support systems straight into masonry or concrete substrates. A pre-drilled pilot hole matched to the screw diameter is still required before driving - cutting its own thread doesn't mean drilling its own hole - but that's the only preparation step needed. Bi-metal construction is what makes direct thread-cutting into masonry possible: a hardened carbon-steel point and thread are needed to cut reliably into masonry and aggregate, since a solid stainless screw isn't hard enough to do that job without the thread rounding off or the point failing to bite, while the stainless body gives the visible, load-bearing sections of the screw the corrosion resistance masonry fixings need over time, particularly on external work. Choosing a Multifix screw over a plug-based system like the Hammerfix comes down to the substrate and the load involved: direct thread-cutting suits denser, more consistent masonry and heavier or more structural fixings, whereas a plug-based system tends to be preferred on softer, more variable, or already-damaged masonry where a plug's mechanical expansion is a more forgiving way to get a reliable grip. Getting hole diameter and depth right matters more with a Multifix screw than with most other fixings in this range, since the thread-cutting action depends entirely on the pilot hole being sized correctly for the screw.

FAQs
Does it still need a pre-drilled hole?
Yes. Although there's no plug, a pilot hole matched to the screw diameter still needs to be drilled into the masonry before driving.

What happens if the masonry is soft or crumbly?
The thread may not cut a reliable grip in weak or variable masonry; a plug-based fixing like the Hammerfix, or a mechanical or chemical anchor suited to weaker substrates, is likely to be more appropriate.

Can a Multifix screw be removed and re-driven into the same hole?
Generally not reliably - once the thread has been cut into the masonry, re-driving into the same hole gives a weaker fix than the first installation; forming a new hole is the safer approach if a fixing needs to be redone.