I want to add a metal roof to my deck, but it is currently flat. It has a perogala roof on it and I want to cover it to avoid rain and add shade. Is it possible to add a pitch to it even if it is slight to help with water drainage? How hard would it be? Thanks for any help.
sure can…anything up to 5 degrees is quite simple
Some pictures would help. Most importantly before deciding on what type of roof and how to install it, you need to make sure the structure meets code to install a roof. Depending where in the country you are located that will vary. You need to make sure the structure will support a roof load as well as a snow load. The pergola will also need to be anchored properly to the foundation for the added wind forces it will now under go.
As far as construction you could add tapered rafters or possibly trusses on top of the perlins to add slope. Another option to consider might be a flat lock, soldered seam metal roof and a gutter, then you would not need to add slope.
Looks like it is built pretty good, I see hurricane clips on the perlins. Can’t see how it is attached at the bottom.
I am assuming you are looking to do it as a diy project? I’ll just tell you What I would do if I was doing it at my house, you need to make sure it meets code in your area.
Remove the 1x6’s laying flat on top of the perlins. Get some 2x12’s the sane width as the 2x6 perlins. Cut the 2x12 to length and find center on the top. Snap lines from your top center to the bottom corners, making a big wide “A” and cut. Place directly on top of the existing 2x6 and predrill and fasten with graduating length screws, 4", 6", 8", 10", home depot sells long timbertek screws designed for treated lumber.
Once they are all on I would add a row of 2x12 blocking at the ridge from one 2x12 to the next to form a sold ridge. Then add some hurricane straps on the insides tieing the 2x12 to the 2x6.
If they are on 16" centers you can use 1/2" plywood on top, 24" will require 5/8" ,or might be different in your area, then install underlayment and your metal on top.
Just an idea of how I would do it if it was in my property and to meet code in my area.