Help with loft insulation before boarding.

[Muzgabrak]

Hi.

I'm trying to create an extra storage using loftzone kit. Went up to the loft to take some measurements, and I've noticed quite a lot of condensation (see pic.). According to the informations I've got, the insulation and roof were fully done approx.5 years ago by council or council contractors. Insulation wasn't laid properly, it was just dropped on top of the ceiling all in the same direction in 1-4 layers. Moved all around and done it properly apart from the eaves. It looks like there's a plastic ventilation membrane all around at the ceiling/slope level. Felt above that plastic membrane is all wet, below dry. There's a little bit of polystyrene stuffed at the bottom of each eave (no soffits, gutter against the cladding), and some uninsulated gap.

My questions are:
Shouldn't that plastic vent? membrane go all the way to the bottom?
Can I insulate the top of the eaves (above the polystyrene and below the vent membrane)?
What are the best options for me to clear the condensation?

Any help, please. I need this done before boarding as it'll block the access. I've tried to take pictures to help, If those are no good can take more.

 

[JohnD]

please see

https://www.diynot.com/diy/threads/condensation-in-loft-answers.160032/

 

[Muzgabrak]

I've seen this and I do tick pretty much all of the boxes. What I don't understand is why felt is wet only above that plastic membrane. I've seen quite a lot of pictures online and on all of these pictures that membrane goes all the way to the bottom of the roof so condensation is removed on top of it. In my loft, there's only a stripe that goes around. Is that how it should be?

 

[foxhole]

Plastic membrane will be trapping moist air increasing condensation , can’t think why it’s there.

 

[Muzgabrak]

I've kept looking for answers and it could be a system similar to this one: https://timloc.co.uk/products/1m-over-fascia-vent/. If the weather's decent this weekend I'll go up and check for vents like in the picture. If I'm right, the only thing that I don't understand is why felt is really wet above that plastic and completely dry below.