R-Panel metal roof over skip sheathing, radiant barrier how to questions

I am installing an r-panel metal roof on a single story 1200 sq. ft house with a 5/12 pitch. I have removed all the old cedar shake. I want to put down a radiant barrier. I have storm guard for the eves, hips, valleys, etc. and deck armor for the field. From what I gather is

  1. I can put down the radiant barrier directly over the underlayment (already purchased)
  2. install fir strips/battens ( what size needed here- 1x1, 1x3, 1x4, 2x4)
  3. install them horizontally
  4. some people say I have to do cross battens as well as running vertically. In this case, the radiant barrier would be suspended between the two battens, which seems like overkill to me but willing to do what is necessary. Also, I am afraid that doing this would raise the roof to high then I would have to fuss with the existing gutters with a piece of angle that didn’t come with the roof trim.
  5. I also have insulation and Therma block available to me. A friend that that does commercial steel erecting says I can help myself to whatever I need.
  6. I believe that I need a way for the hot air to travel upwards since the r-panel has 1.25 inch and a 3/16 raise in it, isn’t that good enough?
  7. what about using inside enclosers? Is that correct?
  8. currently the house has vents under the eaves inline with the wall,(sorry I don’t know what these are called) gable and roof vents but not ridge vent. Should I be installing ridge vent? If so, how to with the metal roof?
  9. If the radiant barrier isn’t necessary please say so. I could always install it underneath, hang from the rafters, inside the attic if that will relieve a bunch of headaches.
    Thank you in advance for helping me out, MJ

PS- If you are willing to address any one of these questions please do. You don’t need to answer everything

There is so many ways to do metal roofs.
When your goal is to keep heat out
Even the sloppiest do nothing methods
Results in much less heat in the attic
Than a asphalt shingle roof.

It is smart to integrate insulation during a metal roof install.
That alone cuts most of the heat infiltration into the attic.
It also gives a perfect new plane for the panels to screw through.
And stops the huge condensation problem.
You wanna use the polyiso with the aluminum looking top on it. And tape the seams.
The insulation doesnt have to be inches thick.
Maybe 5/8 to 3/4.

If you are determined to go the “radiant barrier”
Roll material stuff, than i would say you also need the batons. The 1x3.
The ones with the beveled edges.

By the way, i am very interested in what others experiences have been on this subject.
I hope many share their thoughts on this.
I am always scared i might be doing it the wrong way.
I read some where how if you dont do everything right using the baton technique
The condensation rots the batons out…

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Here is what ive done on these type. Once the shakes are off. Hammer the nails down. I roll out low E reflective. I buy it from metal mart. It’s about 1/4" of foam. White/silver. It comes in 5’ wide roll. Roll it parallel with the panel. It has a selvege edge that sticks to the next roll. You can pull it fairly taunt, and the panels will not sweat into your attic. The foam is bug resistant and it seals around the fastener. All but one, I’ve put the white down and the silver up. I know it’s contrary to techshield, but it’s the customer wanting white to show in the attic, or their open barn, shop. Just an idea.