Lab research facilities are energy intense building types due to the vast amounts of 100% outside air required. With today's concerns over high energyexpenses, reducing carbon footprints, plus efforts to make facilities' green and provide a better indoor environment, reducing both new and existing labfacility energy expenses has become a critical challenge particularly in hot and humid climates such as the Middle East where the cost of conditioning thisvast amount of outside air can be both very expensive and taxing on a GCC country's energy resources. The primary reason behind many labs' highenergy expenses is the minimum ventilation or air change requirements that often dominate the amount of outside air required by these facilities. Thispaper will present a proven Demand Based Control solution to this problem. In this approach that is referred to in the ASHRAE handbook, ratherthan use a fixed air change rate of 6 to 12 ACH (Air Changes Per Hour), real time measurements of the actual lab indoor environmental quality areused to vary the air change rates from as low as 2 to 4 ACH to upwards of 8 to 16 ACH based on the cleanliness of the lab room air. By safely cuttingthe lab air change rates often times by as much as 50% or more for about 98% to 99% of the time, this approach is often cited as the single largest energyconservation approach for many lab facility designs. Furthermore, in new designs significant net reductions in first cost may also be achieved throughreductions in the sizing of the HVAC systems. Finally, by significantly increasing air change rates when contaminants are sensed, improved IndoorEnvironmental Quality (IEQ) can be achieved. This paper will describe this successful approach for labs and vivariums plus discuss the technology usedto implement it cost effectively.