On Heat and Open Windows.

Here in my little corner of England it’s been unusually warm by UK standards today – around mid-30s Celsius I would guess. We’re not used to that sort of heat and so we find it oppressive. But here in my little office the temperature stayed down around 20°. Why? Because I had the windows shut to keep out the heat.

I’ve noticed that most other people don’t do that; they have all their windows wide open, presumably in the mistaken belief that it will keep the house cooler. But how can it? It can’t, at least not during the day when the ambient temperature is high. All it does is let the hot air into the house.

I’ve talked to a few people about this and realised that most people don’t appear to understand the difference between solar gain and ambient heat, and that’s what seems to cause the misunderstanding. I find this odd because the simple principles of heat transference was something I was taught during the early years of high school. Were they not listening, have they forgotten, or did high schools stop teaching useful facts shortly after I left? The situation at night when the outside air cools down is different, of course, but let’s not get complicated.

And what the hell anyway? It’s none of my business what other people do. And they say it’s going to be hotter tomorrow. And I’ll bet it was pretty uncomfortable in central London today. Serves them right for being so self-important.