Traditional wall-mounted insulation systems can be difficult to mount in historic buildings without damage to original interior surfaces and plasters. This can lead to restrictions in retrofitting energy saving measures like internal wall insulation. This poster describes the development of a new reversible mounting system using cyclododecane (CDD), a volatile binding medium. CDD allows the application of different internal wall insulation systems without damage to the underlying wall. A preliminary study using an adhesive mat as a separating layer proved promising, but allowed mould growth because of airflow. To avoid this problem, a fully-reversible system was designed, using CDD in combination with a newly-developed plaster. A case study in the 18th-century Alte Schäfflerei building, now the Fraunhofer Centre for Conservation and Energy Performance of Historic Buildings, tested the suitability of this system in a historic building. Ten different internal wall insulation systems were tested on prepared test fields containing matrices painted with original colour binder systems. Each test field was about 10 square metres in size and included a window with window seals and reveals. Measurements of temperature and RH, and metrical and visual comparative assessments were made on these test fields in order to find out the long-term effect of the insulation systems on the underlying historic lime plaster. This research demonstrates that it is possible to design a reversible interior insulation system using CDD as a protective layer for original surfaces on historic buildings.