re: Central A/C question...

I have about the same sq. ft. single story ranch with gable roof. Was having the same problem. Last summer I added an electric gable attic fan and built a rigid foam insulated cover over the attic steps. My a/c can now keep up and shuts off during the afternoon on the hottest days. Using my local cost for electricity I calculated the fan cost about .20 a day or $6 a month to run.