When they build a 2-story house, why don’t they put the thermostat on the 2nd floor (where the temperature is more variable due to heat transfer through the roof)?

Question

I always try to keep my 2nd floor below 80° but my thermostat is on my 1st floor, so I have to keep changing the downstairs thermostat just to keep the upstairs temperature constant.

*For example:* On a really hot day, I have to set the downstairs thermostat to 72° if I want the upstairs to be 80° but on a mild day, I can set the downstairs thermostat to 76° to keep the upstairs at 80°F.

If the upstairs temperature is bound to be more variable (I assume due to heat transfer through the roof), why not put the thermostat on the 2nd floor?

In: Engineering

Answer 1

Thermostat in the 1st floor is fine; you’re just missing a critical step. 

When it’s hot and you have the a/c on, close the vents leading to the first floor. Then the cold air sinks from above and evens out. 

When it’s cold and you have the heat on, close the vents leading to the second floor. Then the warm air rises up from below and evens out.