grout on the outside between window and stud

[JanneSjo]

I'm installing sliding windows on the patio.
There's a few mm gap between the aluminum frame and the wooden beam.

The window is recessed on one side and flush with the beam on the other side.

Can I caulk between the window and the beam on the outside before I put the casing, or will it cause moisture problems?

It's difficult to get wind paper there, so if I don't caulk, it won't be windproof.

Or is there another way to seal it to be windproof but let moisture through?

Some pictures
First short side full view of the window

Below you can see that there is a gap between the window and the beam. I will put a casing against the beam/window, between the beam and the latch, but it will not make it tight.


Below is a picture of the long side where there will be casing at each window on either side of the post -

Below a close-up of that window

 

[JanneSjo]

anyone with knowledge about this?


can you caulk between the window and the frame on the outside before I install the casing, or will it cause moisture issues?

it's hard to fit wind barrier paper there, so if I don't caulk, it won't be airtight.

or is there another way to seal airtight but allow moisture to pass through?

 

[vojma]

If you only seal on the outside, there will be no "moisture trap".

 

[JanneSjo]

ok I believe that with exterior doors you should seal on the inside, and on the outside, you should not have sealing so that moisture can escape

in my case, it will be the opposite.

but it is a conservatory without heating so maybe it's ok as you write if I only seal on the outside.