Yes, and it is very, very expensive to retrofit. AND normally we don't need it but for a few weeks a year. 2 or 3 years ago, we never even put in the window a/c units. I didn't mean to imply we have no a/c, just window units, and in 11 years the two we have had been fine. The one window that an a/c unit would fit into (that is in our kitchen) would render our porch completely unusable. I'm thinking of one alternative that I don't think husband will approve, but if I get it started he never complains about money I spend.
When you're dealing with old houses (1864), every time you do something another problem crops up. The thing is that this isn't something that happens regularly. We've been here 11 years, and the last time our part of the country had this problem, it was the year my husband was born (1947), so putting thousands into a problem that may just be this year's fluke would be foolish. I am thinking of calling in an electrician and having an area of the house wired so I can put a window a/c unit in the back bathroom (like most old houses, there is a bathroom off the kitchen). I'd like to have an outlet there anyway, and I can cool the kitchen from that window.
Just trials and tribulations of old home ownership. After today the cooking issue should go away. Right now cooking early and eating cold at night works for us. But if this becomes a trend, will be considering options.