I live in a 2-story house built in 1949 that has a forced air heating and air conditioning system. Of the 4 rooms upstairs, the 2 largest ones do not get cool enough. At the same time, the first floor is plenty cool and the basement is frigid. What is the most cost-effective and simple way to remedy this problem?

upstairs too hot, downstairs too cold

But the basement is just right!

:)

I live in a 2-story house built in 1949 that has a forced air heating and air conditioning system. Of the 4 rooms upstairs, the 2 largest ones do not get cool enough. At the same time, the first floor is plenty cool and the basement is frigid. What is the most cost-effective and simple way to remedy this problem?
Have you try reduce the air flow to the basement and the first floor