Fence posts standing directly on tar paper roof

[turbo100]

Hello,
I have a balcony with a railing where the posts are placed directly on a roof covered with thick roofing felt, with an extra layer under the posts to avoid penetration.
The posts are a few years old and made of pressure-treated wood.
Now they are down for painting, and I saw a small rot damage that has been fixed.

Should I treat the posts with any impregnating/rot-protecting solution before painting them?
Should I use some kind of spacer under them when putting them back, which doesn't risk damaging the felt?
They are 125x125
Any tips?

 

[turbo100]

Hello,
I have a balcony with a railing where the posts are directly on the roof, which is covered with thick roofing felt and extra layers under the posts to avoid penetration.
The posts are a few years old and made of pressure-treated wood.
Now they are down for painting, and I noticed some small rot damage that has been fixed.

Should one treat the posts with anything impregnating/rot-protecting before painting them?
Should there be some kind of spacer under them when putting them back, which doesn’t risk the roofing felt?
They are about 125x125.
Any tips?

I'm considering cutting them by 2.5cm and attaching a base around them—as a skirt that the posts can rest on, so the underside of the post is in the air. Then you can just unscrew the skirt parts and replace them in the future.
A skirt made of 22x45 facade perhaps?
What do you home pros think about this?

 

[vectrex]

Slaughter an old (or new) plastic cutting board and saw it into rectangles, say 100x100, which you attach in the middle under each post. That way, the underside of the post will be kept significantly drier.

 

[turbo100]

Slaughter an old (or new) plastic cutting board and cut it into rectangles, say 100x100, which you attach in the middle under each post. This way, the underside of the post will be kept significantly drier.

Sounds reasonable.
I got the idea of using floor tiles in plastic, they have air holes and might work well as a spacer.
https://www.jula.se/catalog/tradgar...golvplattor-och-plastgolv/golvplattor-019171/
Maybe nail those in place and saw around them - too bad they're not black..
Then I just hope they don't melt through the paper when it's 35+ and sunny..