Anchoring to Concrete: Titan HD Anchors and a Rotary Hammer Drill

Scott of Everyday Home Repairs drilled 16 holes in concrete to anchor two brackets for a solar tracker base, and says the job went without a single blowout. His point: most anchoring failures come from the wrong tool, the wrong process and a generic wedge anchor.

Choosing the anchor

In a past poll, thousands of viewers chose among three options: one in 10 picked the Simpson Strong-Tie Titan series, two in 10 used wedge anchors and seven in 10 used Tapcons.

He considers wedge anchors the most likely to fail. A collar goes into the drilled hole and the anchor is tapped in; threads can get gummed up if they run to the end, so he suggests leaving the nut a little proud when hammering. Tightening pushes the wedge out against the insert, which secures it in the hole. He calls these prone to failure, especially for DIYers.

Tapcons have worked well for him, but he has upgraded to the Titan series. He is unsure whether the thread design is the reason, compared with the waves on a Tapcon's first few threads, but says it bites better and has not blown out. Tapcons have blown out for him in the past, which he attributes usually to how the holes were drilled.

Drilling the hole

He calls drilling the most common source of error. Many homeowners default to the hammer setting on a combination drill with the right bit. He says this is not very effective: fine for one or two holes, but with 16 he recommends stepping up to a rotary hammer drill.

In a side-by-side test he drilled a 3/8 in. hole, marking the bit with a Sharpie one inch past the depth needed. The standard hammer drill took two minutes. The rotary hammer drill took 30 seconds, which he calls four times faster. He notes the mark should be measured to the concrete, not the top of the debris pile.

Cleaning the hole

Leaving debris in the hole will probably cause a failure, he says. After drilling about an inch past the fastener depth, he keeps the bit turning in the same direction while a vacuum sucks up the debris pile, then continues vacuuming as he pulls the bit out.

Driving the anchors

Titan HD anchors then go in quickly with an impact driver. His camera overheated, so not all eight anchors on one bracket were filmed, but he did two brackets and all 16 anchors went in secure. He says a rotary hammer drill can be rented.