Are wood fiberboards well suited for thermal insulation?

Hello,

I have been reading in this wonderful forum for some time. Now I have finally managed to register here and I am starting right away with a question.

Our roofer recommended installing an additional intermediate insulation. It should be 160 mm thick and his suggestion is to install this additional insulation with mineral wool and wood fiber boards. He said there is already wonderful thermal insulation in the attic. Our architect was also enthusiastic.

But that costs extra money and with a rough calculation, we are at an additional 3,500 francs.

At the hardware store, an employee said that the mineral wool alone already insulates well. Now I am a bit uncertain and therefore ask here.

What experiences have you had and is it worthwhile to use mineral wool as insulation?

Do the wood fiber boards also provide additional benefits?

These boards are supposed to fulfill their functions for several decades.

Thank you in advance.
Best regards

I believe that the architect was enthusiastic. But against the heat in summer, and I think that is the point. I do not find this additional insulation useful, because other options are available here. At this point, the window areas need to be considered, and often blinds or shutters help here.

But one thing I am also sure of is that these panels increase thermal protection, and now this investment needs to be weighed.

Good luck with that.

Hello Bastian,

He is talking about the roof and not the window front. However, 160 mm is rather insufficient for me.

Kind regards
Regina

Yes Regina, that is correct and what happens next? I am looking forward to your answers

Well, hope dies last. But I think 160 mm mineral wool as the only insulation is a bit sparse, isn’t it?

But I do believe that summer heat protection also plays a role. Most rooms under the pitched roofs are lit through the gable, so that does matter.

Wishing you a wonderful day.

Hey

I'm not an expert, but additional insulation can definitely make sense. It can also be a minimum requirement.

I would be interested to know what thickness is supposed to be installed there?
Kind regards