Latest Discussions : Miscellaneous


04:16PM | 10/01/04
Member Since: 09/30/04
1 lifetime posts
I am replacing the posts that hold up my patio roof. I've poured new concrete pads, and need to drill holes for the lead anchors that will hold my post brackets in place.

Must I let the concrete cure before drilling the holes for the anchors, or is it easier to drill before curing?

My anchors are 1/2" diameter. Do I need to predrill a smaller hole to keep it from "wandering" or is it safe to drill a 1/2" hole right off?

Glenn Good

07:48PM | 10/02/04
Member Since: 09/10/03
314 lifetime posts
Let the concrete cure for at least 3 days before drilling. Waiting 7 days would be best before installing the anchors. Expansion anchors exert a great deal of outward force against the concrete and it takes at least 5-7 days for concrete to cure to 60% of its designed strength. If you install the anchors too early you could crack the slab especially if the anchors are in a corner or near the edge of the slab.

Drilling a 1/4" diameter pilot hole would help with the alignment.


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02:44PM | 04/04/22
Thanks for this information.

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