Hot air rises, and cold air sinks, because of the laws of physics. That means that even if your air conditioner is working overtime, the upper floors of your home tend to get hotter than the lower ones. If you don’t have shady tree cover, your roof will absorb a significant amount of heat from the sun.

Silky Terrier Dog Breed Playing Aro... Silky Terrier Dog Breed Playing Around

Why is it so hot upstairs but cold downstairs?

You may recall from school that the density of the air is affected by the temperature of the air. Because cold air is heavier than warm air, it tends to remain at the bottom of the column while the latter rises. That’s why the downstairs can feel so cold while the upstairs is warm in the winter.