Check and reseal sliding glass doors
Check and reseal windows
Check and Change HVAC Filter
Replace or install weather strips on all exterior doors
Lets talk about the thermal envelope of you home to a lot of you might be wondering what the thermal envelope is. It is the boundary lines of that separate the inside living area from the outside elements. Not having a good thermal envelope will not only make you home hot in the summer and cold in the winter it will also put a strain on your HVAC system causing you to need to run it more and using more energy in whatever season it is. you can start by installing Dual pane windows adding insulation concentrating on the joints of the house(where two corners connect) as well as making sure the subflooring is sealed correctly around the foundation area.