Due to the more and more stringent requirements of the energy performance regulations, thermal bridges at the bottom of load-bearing masonry walls should be avoided. Most of the existing thermal break materials suffer from relative small compressive strength. In order to cope with this drawback a new thermal break unit consisting of high density polyurethane with compressive strength of 6.6 MPa has been developed. At Eindhoven University of Technology a series of tests has been performed for the evaluation of the characteristics of this product. The research project started with concentric and eccentric compression tests on the material itself. In the second phase of the project compression and shear tests on wallettes consisting of masonry and thermal break units were carried out. In order to evaluate the long term behaviour, creep tests have been set up during more than one year at several load levels. Also the fire resistance of the product has been investigated at the Waringtonfire laboratory in Ghent, with positive outcome. As a result this new thermal break unit is ready for introduction into the market.