That said i am looking at installing central air before summer hits.
How to install a cold air return floor grille.
Cut a hole low in the drywall where you want to put your return air grille.
Homes will either have multiple small grilles throughout or a single large grille installed in either ceilings or walls.
Grilles the function of a grille is to pull air from a room to return it to the heating or cooling system.
The main floor has 3 supply and 3 return registers all on the floor but the supply is interior and returns are under windows along the exterior.
Running a metal cold air return duct between studs requires knowledge of both hvac systems and the components involved in framing.
With the right tools you can install a return air duct successfully.
The vent cover or grille usually contains a removable filter and is sized to fit between ceiling joists spaced a standard 24.
Thankfully our climate is pretty temperate here.
There are zero return registers upstairs 3 bedrooms and 1 bath.
Warm air rises and the return will direct that air to the cooler.
Size the hole appropriately to the grille size.
This should give you a hole into the basement.
Through the hole cut through the floor.