I the near future I plan of moving my upright compressor outside behind my shop. I want to build some sort of roof over it. What is the best way to attach and seal a roof to a corrigated metal wall?

My first guess would be roofing tar at the seam. stuff is pretty stout and is designed to adhere to metal and resist weather. Its the stuff you use around chimneys to seal the metal flashing.

If it ever springs a leak down the road, simply work some fresh tar into the cracks.

This 'tar' you are talking about is referred to as either 'fibregum', 'plastic cement' or simply 'roof patch'. This stuff is temporary at best.

It's not the correct way to seal in the panels. The right way is to make a horizontal cut in the wall cladding and slip in a metal wall flashing. It would slip up in behind the panel abkout 4" and come down the slope of your new roof about 4".

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\</pre>[/QUOTE]^^^ Kind of like this, but at a more gradual slope to match your new roof line.

I'm a commercial roofing and cladding contractor.
Do it this way and you'll do it once, ZERO maintenance.