Thermal systems installed in museums should guarantee the maintenance of the optimal hygrothermal parameters ranges for the conservation of their collection materials. Considering the preservation of historic buildings, according to their historical and landscaping constraints, not all the thermal system typologies could be installed in these buildings’ typologies. Therefore, the main aim of this paper is to present some indications for the choice of the best thermal system solutions for a considered historic museum building, called Vittoriale degli Italiani, in the north of Italy, taking into account their installation feasibility and their related environmental impacts. The methodology includes a monitoring of the current hygrothermal parameters as well as the assessment of design heat and cooling loads related to the maintenance of the optimal hygrothermal parameters ranges for the conservation of collection materials. In addition, a Life Cycle Assessment (LCA) of each selected system typology is considered for highlighting the most eco-friendly solution among the suitable ones. The obtained results highlights the feasible thermal system solutions able to maintain the hygrothermal parameters between the optimal ranges with a lower environmental impact in the Vittoriale degli Italiani historic museum building.