Thermostatic Radiator Valves (TRV's) are a great way to control different heat levels in different rooms.

The valve senses air temperature in the room and works by controlling the flow of hot water to the radiator. When the room temperature has reached the desired level the valve is shut, this boosts the flow of hot water to the other radiators on the system and in turn will make the boiler shut off quicker. Making the heating system more efficient and use less gas.