Wood furring attachment to CMU
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We are renovating a building where we are adding 2″ of rigid foam to the exterior of the concrete masonry unit walls. So the wall system will be as follows from the inside surface to out;
- 8″ CMU
- 2″ Polyiso
- 1x Wood furring
- Fiber cement siding
The contractor does not like the idea of having to pre-drill holes for the fasteners to support the wood furring. Has anyone ever used a powder-actuated fastener in this application? Hilti does have a fastener long enough for this application, however just wondering if anyone has actual experience with this fastening method.
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Replies
Joshua,
As far as I know, screws are the preferred method. I have not tried to use powder-actuated fasteners for this application.
I suppose you could always call the technical department at Hilti and discuss your idea with them.
Yeah, I spoke with Hilti, and they have not tested that specific application, however they gave me testing reports on pull out and shear strengths for my structural engineer to review.
Joshua,
It sounds like you are taking the right approach. It's good that you have a structural engineer on the case.