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At inspections here in Chicago I frequently see termination bars pulling loose from the interior of CMU parapet walls.

Most of these are attached with pin drive fasteners, it appears based on what I've seen that these often have poor holding power in CMUs.

Any opinions on these fasteners?

Recommendations for superior alternatives?

Thanks.
 

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Tapcons are not recommended for hollow concrete block. They simply will not bite in most cases. Most hollow concrete block is dry cast and extremely cheap and flimsy material. The tapcon threads will rip up the weak flimsy concrete on the first try.

We always use the expanded lead anchors (nail-ins) and make sure to fasten every hole. It's still not perfect, but it's an imperfect situation dealing with the crappy concrete block builders like to use. I haven't had a problem doing it this way. I have found it simply impossible to use tapcons. Perhaps there is another screw I am not aware of.

It's better to wrap the entire wall before the coping is installed if and when possible. Another alternative is a coutner flashing with reglet. Or in other words a counter flashing bent in such a way that it is insert into the wall mortar joint.

It could also be the cheap P.O.S. block the builder used, maybe not the fastener. I hate concrete block with a passion. It's like a sponge. Junk.
 

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We use lead or nylon hit anchors, if you used tap-cons it would take for ever. Plus if you have ever used a Phillips headed tap-con (flat headed) they strip out super easy.

What kind of roofing system have you seen this on most. Ballasted EPDM? I ask this because once the rubber starts to shrink there is little in the way of any fasteners that will still hold it to any type of wall.
 

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Tapcons are not recommended for hollow concrete block. They simply will not bite in most cases. Most hollow concrete block is dry cast and extremely cheap and flimsy material. The tapcon threads will rip up the weak flimsy concrete on the first try.

It's better to wrap the entire wall before the coping is installed if and when possible. Another alternative is a coutner flashing with reglet. Or in other words a counter flashing bent in such a way that it is insert into the wall mortar joint.

QUOTE]

I've had luck with Tapcons in hollow block. Its all about the correct sized bit and the correct depth in case you hit a solid area. Yes they take way longer, Yes the square drive are better. Expansion anchors can work too, I would reccomend using the ones with the screw heads so if they dont set right you can unscrew them. I would try tapcons first. TO me its the right way to do it. But maybe I havent used them in cheap block. Do some test drills and see.

Also 100% agree with Grump about covering the wall if possible, CMU block is the worst.
 
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