For an engineer, equilibrium is something to be attained – at home, at work, on travel. Equilibrium means things are equal. At peace. Not changing or frenzied. One equilibrium issue which is always running through my mind in winter is thermal equilibrium of our home.

ΔHeat = 0

Or, put another way,

Heat In = Heat Out

It seems simple enough. The more heat is transferred out of the house, the more the heating unit will need to transfer heat in to the house if equilibrium of the home temperature is to be maintained. I sit there and see the heat transfers take place and plot how I can affect this equation. How can I prevent heat from transferring out of the house, therefore reducing the need for more money being spent to add heat to the other side of the equation.

This is why we insulate our homes, seal the cracks around our windows, and yell at the kids to “Shut the door!”