I own a house that is less than 3 years old, the roofs lost on ceiling suspended plasterboard are insulated by 20 cm of glass wool unrolled. Today I want to complete this existing insulation, what can I consider? Do I have to keep the same type of insulation?
I am always in favor of product consistency.
To reinforce your existing insulation, simply unwind a second layer of Naked IBR Building Felt that you can then cover with particle board or plasterboard. So your floor will be flat and you can use this surface as attic.
See our fact sheet on THE SOIL INSULATION OF THE ATTIC.
This may interest you