Porch roof decking

[markert2523]

I'm trying to decide what to use for my porch roof decking for the two family cabin.


The porch roof will have exposed joists 24" OC, so you will be able to see the roof decking.  I like the look of planks and am wondering what material I could use.  The roof decking will have metal roof over it and I really don't want to see screws protruding through.  Of course cost is always an issue.

Is it OK to use plank material?  If so, does it have to be tongue and groove?  Could I just use 2x6 dimensional lumber?

Appreciate any input.

[MushCreek]

Any 2X material will work- metal roofs are commonly installed over purlins as much as 2 feet apart. The exposed tin is a nice look, but it will be much louder in the rain, and it may be prone to condensation under certain weather conditions. I would compare the cost between T&G 2X6's and regular ones. For a nice finished appearance, the T&G would look best. You should use tar paper over the decking, and regular 2X6's may shrink enough to be able to see the tar paper. Since it will be exposed, make sure you keep the rain off of your work until you get it weather proof to prevent staining.

[Redoverfarm]

Either one should be prefinished before installing.  It's difficult to get a decent finish once it is installed.

[Don_P]

With 24" oc spacing you can use 3/4" T&G, I've run a layer of osb over that to keep roofing nails from poking thru. With 1-1/2" thick T&G you can space the rafters wider and use 4x for them, looks nice. I prefer prefinishing as well.