Around 3,000 watts is a common starting point for a 300-square-foot room under average conditions. Large windows, poor insulation, high ceilings, or colder climates may increase the required output.
For a full breakdown on calculating heat requirements for baseboard heaters, read our Baseboard Heater Sizing guide.
Yes. You can use multiple baseboard heaters to reach the required total wattage and improve heat distribution. However, the circuit, thermostat, wiring, and combined electrical load must be properly sized for the installation.