What type of horizontal purlin/furring under my metal roof?
Dielectricunion| Posted inGeneral Questionson
I’m agonizing over what to use under my metal roofing. I need something that will lie over my two layers of foamboard to take screws for attachment to rafters and also something to attach my exposed fastener metal panels to.
I’d like to avoid adding another 1.5″ using 2×4 but most furring strips I’m finding are total garbage and only come in 8′ lengths. Originally, I had planned on using 1/2″ OSB or plywood, but that will be very expensive and wont allow me to shim out any sags easily. I wish there was some affordable synthetic material I could use.
Any preferences for a strapping method here?
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Replies
http://mattrisinger.com/venting-a-metal-roof-with-rigid-foam-underneith/
Looks like he used 1x4 set at angles and end-to-end when needed. Scroll to the two minute mark in the video.
Dielectric,
Most roofers use either 1x4 or 2x4 strapping (purlins).