ᐅ Roof Insulation in the Attic Space for New Construction

Hello everyone,

We have been proud owners (well, together with the bank...) of a semi-detached house in Bavaria, near Munich, for a year now and have some questions about roof insulation.

First, the current situation: we live in a semi-detached house (ground floor + first floor + attic as living areas), built in 2014 (solid construction, 365mm (14 inches) brick). There is an attic above – without windows, only two opposite ventilation pipes through the roof, not converted or insulated (the ceiling/floor towards the attic is insulated though), no heating, accessed via a pull-down ladder, almost always closed. Currently, this space is used for storage, but it is cold and partly damp. This exact area is now planned to be insulated. The ceiling/floor to the attic is already insulated.

The goal is to create attic/storage space that is not damp (before blocking the two ventilation pipes through the roof, we even had some mold growth, although very little) and where the temperature remains constant.

Will this be possible?

Can I also save energy in addition?

Will this (due to partial double insulation) make the attic warmer in winter and cooler in summer?

What should I consider regarding air circulation in the attic – since there are no windows there…

I have read and understood the instructions on how to insulate. That is not the issue.

The question is: should I do it or not? Will it bring the desired results?

Thanks in advance for any answers, tips, etc.

Best regards,
michael1978

You should be careful here. Incorrect construction can quickly lead to serious structural damage.
Topic: dew point, ventilation, etc.

What is your current roof structure?
Underlay membrane, or wooden sheathing with a secondary waterproof membrane?

Hello, the roof according to the building contract: made from structural timber grade II, impregnated, with Erlus E58 roof tiles, substructure made of Pavatex Isolar wood wool boards 35mm (1.4 inches).
Before the roof tiles were installed, a black membrane was rolled out. Inside the attic, you can see the insulation of the upper floor roof sections in the corners.
Attached are some pictures.
Regards, michael

And here is the attic

There is no vapor barrier or similar in the attic, right?

If this were my house, I would be very careful about making any changes here. I would have the construction details planned by an architect or engineer!

The devil is in the details, for example, how the vapor barrier is connected, and so on.

Well, as the pictures show: roof structure, followed by Pavatex panels, then a battens framework for the roof tiles, and finally the roof tiles themselves.

From inside, you can only see the Pavatex panels in the attic – no membrane.
Attached is a picture of the roof from the outside, before the roof tiles were installed,
and two pictures of the attic ceiling.