Heat Transfer: Insulation

Insulation is added to a system to decrease the rate of heat loss. In a system operating at steady state, if we increase the thickness of insulation, will it decrease the rate of heat loss?

For a steady state system, the heat in to the system should be equal to heat out of the system. So, by increasing the thickness of insulation will not decrease the heat loss. For example, if we are heating a copper disc with a 50 W heater, under steady state 50 W heat will be lost to the surrounding. If we add insulation on the sphere, the heat lost to the surrounding must be 50 W to make it steady. Then, heat loss has not been reduced. But by adding insulation we can increase the temperature of the system without losing more heat, i.e. if the temperature of the sphere was 40 °C with 50 W heat input earlier, by adding more insulation we can raise the temperature of sphere with same amount of heat input.