As you look up from inside the attic into the underside of a roof-mount power fan which direction do the fan blades rotate: clockwise or counterclockwise please?

The rotation of the power fan blades depends on your vantage point.

For all of our roof-mount power fans the fan blade will rotate counter clockwise when looking at the back side of the motor; clockwise rotation when looking at the shaft side of the motor; and counter clockwise when looking at the rear housing.