I made a small concrete patch along the edge of a room that I would like to set a PT 2x4 base plate on for framing. I prefer drilling and screwing with a lead anchor over using power actuated nails.

How soon after setting is concrete ready to be drilled? Is it enough to just dry it (like 24 hrs) or does it need more?

  • Wondering why didn't you just put the base plate down while it was wet? – DMoore Mar 23 '20 at 17:12
  • Because I want to drill it in – amphibient Mar 23 '20 at 18:06
  • Wet anchors are better and really they are easier. – DMoore Mar 23 '20 at 19:14
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    What good is a wet anchor after the pour? – isherwood Mar 24 '20 at 15:36

If you drill too soon after pouring I've found that it tends to flake and crumble around the drill bit giving you a much larger hole than desired.

After 24 hours, which makes it fairly hard, you should have no trouble at all.

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    I'd hold off on the expanding anchors until it's had ample time to cure. At least a week depending on conditions. You run the risk of splitting the concrete if the hole is near the edge or a joint. – jwh20 Mar 23 '20 at 19:24

You can drill the hole after 24 hours, but it would be better to wait an extra day. In addition, the insert you use to hold anything down will readily break free if you tighten it down, even after 2 days. It would be better to wait a week before any kind of real torquing down of any kind of fasteners.

If you are only needed to keep a plate from moving sideways, and not needing to rely on any withdrawal strength then it will work earlier, after 2 days, as long as the screws are not cranked down on.

  • You are right but is what is the deal with not using a wet anchor??? – DMoore Mar 24 '20 at 3:30
  • Not familiar with the term wet anchor. Unless you mean anchor bolts set while the concrete is still wet, I never heard of the term on all my days. It sounded like that the pour was already done, so anchor bolts would be a moot point. – Jack Mar 24 '20 at 3:54

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