Building renovation is a major challenge in Europe with more than 200 million of existing buildings to renovate. Generally, ETICS (External Thermal Insulation Complex System) is claimed as being the most efficient system especially for tackling thermal bridges and keeping thermal inertia. Nevertheless, this system cannot be applied to some existing buildings, especially those having a facade with a high architectural character. In this communication, a slim thermal breaker (STB) for indoor use, made of a VIP protected with PU foam and a finishing board, is presented. A mock-up has been built up in order to investigate the efficiency of the thermal breaker for partition wall. The experimental results and the simulation have shown that the use of this slim thermal breaker (STB) yields a reduction of around 30% of the whole U-value whereas a reduction of 50% is obtained using ETICS. (C) 2014 Elsevier B.V. All rights reserved.