A thermal modernisation programme covering several buildings needs a common assessment method and separate solutions for each property. A school, a residential building and a commercial unit differ in operating hours, the condition of the building envelope and how the services perform. On Izoprofil.eu we describe how to prepare the order of renovations: gathering data, identifying urgent defects, selecting the scope and checking the results once the works are complete. PIR boards can be one of the insulation materials, especially where the geometry of the existing detail limits the space available for layers. Their suitability, however, is determined by the requirements of the specific building element. A shared schedule of the investment helps compare the needs of the buildings without attributing the same savings to all of them. The reference point should be energy consumption together with a description of comfort and how the building is used.