We're lucky in one respect. Because this house is extremely well insulated it takes four or five days before the house itself starts to heat up and we have ceiling fans which help keep things cool. We did succumb to installing evaporative air conditioning a while back but we only have to use it when a heatwave goes longer than four or five days or is excessively hot - the year we hit 43° on the second day of a heatwave at the beginning of February was one of those occasions.
Weather like this takes a toll on the garden and I've just been out putting shade cloth covers over the more delicate plants like the lettuces. The summers here are definitely getting hotter and I foresee a time when the entire vegetable garden will have to be roofed with shade cloth from November to February. Not this year, though, although I may have to rethink that if things if the temperature keeps rising.