Reduce use of lights and appliances avoid generating additional heat upstairs.
To avoid hot from 1st floor rof.
Also adding an attic fan will help cool things down by circulating the air up there and decreasing the amount of hot air reaching your second floor.
The less common answer but just as critical as the first one.
You can even air seal your attic to prevent heat from seeping in.
In other words closing the blinds essentially prevents your home from becoming a miniature greenhouse which is.
If the upstairs floors have few windows and a lot of hallway space between fenestrations the whole floor s airflow can suffer.
Department of energy the surface of a cool roof reflects more sunlight and releases more heat than a so called hot or dark roof.
We have a similar issue in our house.
A cool roof is a roof designed to maintain a lower surface temperature in bright sunshine than a traditional roof source.
The way i see it you have 2 options that will help.
As simple as this tip may seem family handyman notes that up to 30 percent of unwanted heat comes from your windows and utilizing shades curtains and the like can save you up to 7 percent on bills and lower indoor temperatures by up to 20 degrees.
Hot air doesn t just rise it actually seeks out colder environments.
Keep your blinds closed.
Remember all these are minimalist and eco friendly approach to relieve from hot climate.
High temperature during night is not due to atmosphere but the heat radiation from the ceiling that stores all the heat.
Painting the roof white will not help during the evening after the sun goes down.
Heat seeks out cold.
1 put a rubber coating on the top of the roof rubber is an excellent insulator.
Add extra insulation to your roof and attic.