The Integrated Roof-Top Greenhouse Building (IRTG) is stemming from the conventional roof-top greenhouse. Thanks to the carbon offset due to the hosted plants, IRTGs offer us an effective tool able to oppose the global warm-ing, if applied at a large scale. IRTGs are able to harvest local renewable energy resources (geo-thermal, solar, wind, etc.), to store them and to manage them in an integrated way with the water resources. Besides the CO2 management, already described in the literature we consider and the O2 flow. A two ways ventilation system is conveying O2 enriched air from RTG to the building and CO2 enriched air from the building to RTG. A tight symbiosis humans-plants is built such way. This multiple-input-multiple-output system is highly nonlinear, temperatures and gas concentrations being interdependent, which is hardening its automated control. A generic model of this system, taking into account the air exchanges between greenhouse, building and environment is presented, along with a self-adaptive fuzzy-interpolative controller. Given the necessity of the Intelligent Control, we adopt a new term: the Intelligent RTG (iRTG).