Anchors into limestone 1

[milkshakelake]

I’m concerned about using the kerf anchors in this nontraditional way, ¼” edge bearing, and moment caused from wind suction/push. The kerf anchors (1/4" plates/angles) will be attached with epoxy, which is normal, but I don't usually go into the depth of the stone; usually it goes into the edges. I’m not sure how the limestone will react to all this. Thoughts?

 

[jjl317]

Stone cladding engineer here - generally kerf anchors are NOT attached with epoxy, but rather a sealant, which is a more flexible and forgiving connection (especially if done in the field), with the kerf anchor only resisting loads perpendicular to kerf/anchor tab (i.e. right/left direction on mid-height anchor). For a "back of stone" connections, generally some sort of mechanical or epoxy connection utilizing threaded rods (Type 31, Fischer style undercut anchors, or bent rod and epoxy) are attached to the back of stone first, often as part of a two-part anchor, then attached to the substrate. This is certainly not a particularly clean condition, though jambs like this seldom are.

 

[milkshakelake]

I don't know if it's advisable or not, but I try to avoid the type 31 anchors because of drilling the difficult radiused slot. I'm not really familiar with how bent rod and epoxy works with stone; I've seen dowel anchors. But I like the idea of undercut anchors. I'll probably use a Keil anchor instead of Fischer but it's basically the same thing. Thank you, jj! This was driving me nuts.

 

[jjl317]

No problem - and I wouldn't sweat the Type 31 slot - I have used 1000's of them - special tooling makes it pretty simple / cost effective to create - attached is link to a video of an example - though the Keil / Fischer are a great option also

type 31 stone anchor video - Search Videos

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