@storiesoferne True, the roof is essential when building a house, and fortunately here it is very well installed and has good safety measures.

Initially, this structure was designed to have tongue-and-groove paneling installed under the main roof sheets, but for reasons I still don't fully understand, this material never arrived. Then a friend kindly offered to give me a considerable discount on the installation of PVC, and given that this was a unique opportunity and I didn't really have much of a budget, I decided to go ahead with it.

I have gradually learned about everything related to design and construction, since this is new to me and, to be honest, the style of construction here is quite basic, so insulating elements such as those you mention are not very common.

Despite everything, I can tell you that in terms of temperature control, this design is working very well thanks to the air conditioners, and although in other latitudes that would translate into a considerable expense in electricity bills, here in Venezuela this service is super cheap, which is an advantage. Greetings and blessings!