Drop In Anchors

Drop in anchors are about as straightforward as fixings get, but get them wrong and you will know about it. These are internally threaded expansion anchors designed specifically for use in solid concrete. You set them with a hammer and setting tool, they expand against the bore of the hole, and they are not going anywhere. Available in M6, M8, M10 and M12 sizes, with box quantities to suit both one-off jobs and bulk trade use.

The construction is all steel throughout, which matters for two reasons. First, the load capacity is what you would expect from a fixing going into structural concrete. Second, and increasingly important on commercial and public sector work, these anchors are non-flammable. They conform to BS 7671 18th edition requirements, which specifies that wiring support systems must use materials that are unlikely to collapse prematurely in a fire. If you are installing cable management, trunking brackets or containment in a building where fire performance matters, these are the correct anchors to be using.

Where Drop In Anchors Get Used

One detail worth knowing: this standard version can be set below the surface of the concrete, not just flush. That means you can recess the anchor and use a longer bolt, or simply keep the fixing out of sight where the application calls for it. It is a small thing, but on finished surfaces or architectural concrete it saves a lot of awkwardness.

Once set, the anchor accepts a standard metric bolt or threaded rod. That flexibility is what makes drop in anchors so common across electrical, mechanical and structural trades. You are not locked into a proprietary fixing system. Any M6, M8, M10 or M12 bolt will do the job.

These are sold in boxes of 50 or 100, and in bulk quantities of 1000 for those who go through them at volume. Roofers, electricians, mechanical contractors and groundworkers all tend to keep a stock of these on the van.