The heating, ventilation, and air conditioning system (HVAC) and the electrical system play a part in every basement remodel, and plumbing (for a bathroom or laundry room). Almost always does. So before going with a remodel, checking out each system is important.
In most newer homes, the furnace and air conditioner are sized to include a finished basement. Those in older homes are generally up to the task, Al though you may need some supplemental heat. Codes require that certain amount of air be of the furnace.
The electrical service panel in newer homes is usually adequate for a basement remodel. An older home may need new higher-amperage panel to service the additional demands of a remodel. In general, if your panel has fuses, you will need to upgrade your service and replace the panel with a circuit-breaker panel.
If your is already a circuit breaker panel, see if there are enough blank knockouts, below the installed circuit breakers to accommodate the new circuit you plan.
Newer homes are often plumbed to allow easy installation of a basement bathroom. These bathroom “rough-ins” usually include drains for a toilet, a tub or shower, and a sink. A 4 inch round PVC sewer line, capped at floor level or a bit above, accommodates a toilet. A drain and vent stack running from the floor to the ceiling served the sink. Nearby should be a roughly 12″ square plastic cover set in the floor. It protects a drain line set below the concrete for a bathtub or shower. Some tube rough ins are thinly covered with concrete. You can find these by tapping on the surface of the concrete with a hammer. Solid concrete has a flat, dull sound. As you tap, you will hear the recess where the rough in hides as a change in the pitch.