London Plan is the London mayor’s Spatial Development Strategy. This strategic long-term plan comprises of proposals for different aspects of change within the London boundary. Furthermore, the proposals include chapters outlining adjustments in each facet. Policy 4A.2 reflects the Climate Change Mitigation scheme. Some consultations and research works have been performed to this point, but an extensive cost assessment has not been done. This paper reflects a financial assessment by means of Influence Diagrams based upon the London Plan policies 4A.X.