What is the proper etiquette for changing the temperature in a home or space that isn’t yours? Is it OK to just walk over to the thermostat on the wall and tweak it just a few degrees, maybe flip on the heat or air conditioning? In my humble opinion, no, it’s not.

I’m ranting because I recently had a bunch of guests over for dinner, and one of them messed with my thermostat. I didn’t realize it until the next day, but at some point, someone had cranked up the temperature about six degrees warmer than I usually keep it. As soon as I noticed, I was ticked off, but why? Why would something that seemingly trivial annoy me so much?

So I thought about it, and I came up with two reasons why it rubbed me the wrong way. First, I felt like it was an invasion of privacy to change something in my house without asking. I mean, you wouldn’t walk into someone’s home and start adjusting the lighting, would you? How about pruning the potted plants? Rearranging the furniture? Adjusting the temperature on the water heater? No, you probably wouldn’t do any of that, and that’s because it’s not your house.

Second, there’s the potential cost that can come from tampering with someone else’s thermostat. I didn’t realize how the temperature level could affect my utility bill until I received a punch-in-the-gut $200 gas bill in January. At that point, I decided to turn the temperature in my home (which was usually set at 69-70˚F) down to 66-67˚. The next month, my gas bill was just under $170, and though other variables could have also affected the bill slightly, I know that difference was largely due to using the gas-guzzling, inefficient furnace less often. So, before you crank up the heat at your buddy’s house because you’re chilly, think about the money you might be inadvertently taking out of his or her pocket.

I know it may sound nutty, but I also know I can’t be alone in this. Does anyone else get peeved when someone tampers with your home’s thermostat without asking? Or am I just a little too protective of my HVAC system and my home?