Vent winter door installed

Whether you desire to insulate your crawl space or you do not, you still have the option of using the sealer door.  This view shows he sealer door and the summer door inserted into the face plate.  There is a simple rule of thermogenics that says hot goes to cold.  So any heat that your furnace puts down into the duct work which runs through your crawl space will be sucked out of the crawl space through any vent that is not sealed if there is a difference in temperature in your crawl space and the outside temperature.  Our simple philosophy is to keep as much heat as possible in the crawl space where it belongs.  Your furnace won’t run as often or as long to maintain your desired room temperature.  Your subfloors will be warmer and your heat bills won’t be as high.  Theory is theory but common sense says that these are true facts.  A sealed and if so desired insulated crawl space vent or vents will keep more heat from being sucked out of your crawl space than a vent that is mechanically closed but not sealed.