Originally Posted by slumlord
Originally Posted by alwaysoutdoors
Originally Posted by slumlord
Get those shingles off, get a good view of your decking, make sure nothing is rotten.


If all good, cover with #30 with rag felt, mark the rafters and commence to nailing on 1x4 or 2x4 lattice.

Allows for a solid piece of meat to fasten your new metal roofing to.



I've done a couple dozen like this^^


That screwing metal to shingles is a half ass deal. Only if youre lucky will any screws hit a random rafter. Otherwise your punching into brittle 3/8" to 1/2" plywood.
About like zipping screws into a pumpkin rind.

Lattice is not required if you have decking already. Just staple down 15 pound felt and then screw the metal directly . Lathing , lettuce or whatever you call it in your NoW is not required or needed.


I don't care what the requirement is, or even if there is one.

If I walk around on a shîtty, 20 yr old cooked-out mobile home roof with dry rotted 3/8" plywood on 2ft truss centers. I can assure that wimpy, crunchy 3/8" plywood isnt much of a viable medium to hold a screw driven into in it.

So, thus I "like" and "encourage" people I've done these jobs for opt for horizontal furring of 1x4 spf.

The only way I would go directly back onto bare plywood, would be if the house's attic was well ventilated to begin, the structure was 10 yrs old or less AND it had 1/2" 3ply cdx ply.

Again, check out the plywood, even better if the house rafter are on 16" centers, cover it with 30 or 15. (30 is a personal preference)






I see what you mean: install the purlins and remove the decking from the equation. I absolutely wouldnt put new materials on a chitty structure either. My way assumed the decking was inspected and repaired as needed . Thats the correct way instead of leaving chit there and going over the top of it.

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