Thunderbolts – Multi Fixing Hook Bolts

If you need to hang something from masonry and you’d rather not faff about with plugs, sleeves or resin, hook bolt thunderbolts are the sensible answer. The Thunderbolt hook is a self-tapping masonry screw with a formed hook at the head, so you drill a pilot hole, wind the bolt in, and you’ve got a fixing point that’s ready to take a load. No nut, no washer, no waiting around.

The way it works is simple enough. The hardened thread cuts its own groove into the substrate as you drive it, so the masonry itself becomes the nut. That’s the same principle a wood screw uses in timber, just applied to concrete, brick, block and stone. It grips along its whole embedded length rather than relying on expansion at one point, which is why it behaves itself near edges and tolerates being fitted closer together than a lot of expansion anchors would allow.

Where Thunderbolt Hook Bolts Get Used

Hooks are the go-to for anything that hangs. Think suspended cable trays, conduit runs, lighting, banners, temporary signage, pipework supports, netting, sheeting and holding off lines or chains. Electricians and sparks use them constantly for overhead fixings, scaffolders and event riggers like them for quick anchor points, and maintenance teams reach for them because they come out again without a fuss. Fit one, hang the load, remove it when finished. The hole is the only evidence you were ever there.

The hook pattern is also handy where a standard hex head would be awkward. You get a ready-made loop to take a shackle, S-hook, wire or rope, rather than having to fabricate something or add a separate fitting. Saves a bit of kit and a bit of time.

M6 x 50mm and M8 x 55mm

The M6 x 50mm is the lighter-duty size, suited to cabling, small fittings and general hanging jobs where the load is modest. The M8 x 55mm is the one for heavier suspended loads and anywhere you want a bit more margin. Both are sold in boxes of 50, which is a fair few hooks, but anyone who’s run out halfway up a ladder will tell you that’s not a bad thing.

Installation uses standard sized masonry drill bits, so there’s no specialist tooling to buy. Drill the hole, clear the dust, and drive the bolt home with a suitable driver or socket. That’s about the extent of the technique. Because they’re fully removable, they work equally well on temporary installations where you need the wall left in reasonable shape afterwards.

For contractors buying in volume, the cost per fixing is hard to beat when you compare it against chemical anchors or sleeve systems, and the lack of consumables to keep track of makes life easier on site. Always check the load requirements for your application and the condition of the substrate, as soft or hollow block will not hold like solid concrete.