ᐅ Renovating Roof Structure: Insulation Between Rafters & Humidity-Controlled Vapor Retarder

Hello everyone,

Current situation:

A 90sqm (970 sqft) single-family house roughly built in the 1960s with ground floor and first floor (+ an uninsulated attic).

Roof structure: Tiles -> roofing felt (probably) -> wooden sheathing -> aluminum-faced mineral wool insulation (already damp/soft).

Since I want to renovate everything upstairs, replace the old OSB extension and wooden felts, and install a roof window and drywall, here are my thoughts after already reading quite a bit.

Primary goal: To preserve the building structure and avoid mold inside the house.

Therefore, the plan:

• Remove any extension
• Remove aluminum-faced insulation
• Install insulation between rafters using stone wool or glass wool
• Use a vapor retarder (one that can redirect moisture back inside during summer)
• Install drywall

What do you think?

Knee wall

Aluminum-faced insulation:

In the last picture of the attic, you can see roofing felt on top.

Apparently the forum was sold, as there is now a lot of intrusive advertising and the appearance has significantly worsened.