How to improve the roof insulation
This tile is called "Rav Reaf" and it is designed for roofs with a moderate slope.
The shingles colors have consequences on the roofing insulation.
Such a dark color would absorb a lot of radiation and pass the heat into the space below the roof.
Therefore, this selection is incorrect. There are many other brighter colors available in the market. The insulation level of the roof depends on many components: the color of the tiles, type, and thickness of thermal insulation, roof ventilation.
All these elements are essential and cooperate.
You can not rely only on one of them and neglect one or more of the other.