Sizing your AC and heating—do you crunch numbers or just wing it?

"Official load calcs are a solid starting point, but they're not gospel."

True enough, but honestly, I've found the official numbers to be pretty spot-on most of the time. The few times I've second-guessed them and sized down slightly (thinking I knew better), I ended up regretting it on those peak summer afternoons. Sure, insulation and windows matter, but the calculations usually factor in worst-case scenarios for a reason.

That said, I get your point about oversized units short-cycling—seen that happen too. But I'd rather err slightly on the side of caution than have my AC struggling when it's 100 degrees out. Maybe it's just me, but comfort beats efficiency by a small margin every time...