Calvin Coolidge sat on the porch of the White House in nice weather for three reasons.
The first was that it was hot, and there was no air conditioning back then to stifle the heat that builds up in houses made of cement, brick and masonry baking in the sun all day. Porch sitting was a sensible and customary thing to do in the evening while you waited for your house to cool down so you could go to bed.
The second reason was that he was a cigar afficionado. He would usually smoke 3 cigars a porch session, and even back then, folks preferred to not have their houses smelling like strong cigar smoke.
The third, and most important, was that Coolidge had learned from campaigning with Warren Harding that being seen on your porch and occasionally chatting with people made for great politics, and was in effect a campaign all by itself. Tourists would come by in the hundreds and stare at the President on the porch in the evenings and he would stare back at them, equally curious, and throw in an occasional friendly wave. Folks then went home said they "saw" the President. It was a huge factor in his popularity, and it all came from doing nothing, which was something he turned into a masterfully political art form. In 1928 though, Coolidge decided not to run for President again, and so a large part of why he sat on the porch went away, and cigar smoking was mostly adjourned to the Green Room inside the White House.
