Shelter from the storm

There's a crazy thunderstorm going on outside, but I feel safe. My windows are good enough quality that the sound of the thunder is muffled. My air conditioning is working beautifully, so even though there's a rainforest-like humidex of 42 degrees outside, it's a brisk freon-tinged 24 in here. The weather is not going to get me; I can just sit back and enjoy the fireworks.

When humanity first evolved, they wouldn't have felt safe from the thunderstorm. The best they could have managed is to hide under a tree (yeah, brilliant idea) or in a cave. Even once they started building structure, they wouldn't have felt safe right away. A teepee or a longhouse or soddie isn't going to make you feel completely safe from the storm, even if it does keep you a bit drier. But on the other hand, if they were living in the best structure technologically possible at the time, they might have felt safe. Someone in, say, the 19th century probably wouldn't consider it a failure of their housing that they didn't have air conditioning.

So I wonder how far into human evolution it took before housing reached a level where people felt safe in a thunderstorm? I wonder how long it took before the majority of the population was living in a place where they felt safe? (Obviously this still varies around the world, but I'm thinking there was a time when the British royal family was feeling safe in Windsor Castle while the proles down the street were scared in their thatch-roofed cottage, whereas now most people probably feel safe in flats in London.) I wonder if, 100 years from now, people will be shocked that I could ever feel safe in this apartment?