Research Work on Outside Sprayed-on Cellulose Insulation Covered with Plastering

This research work was done to expand knowledge about outside sprayed-on cellulose insulation application focusing on mechanical and physical properties respectively. Various spraying equipment was used for applying cellulose layers onto brick walls. These spraying experiments indicated that the general performance of the widespread common spraying methods or techniques is rather poor as far as achievable shear stress parameters are concerned. In the testing also glue or bonding agents were used to improve the mechanical properties. Material tests were performed using a tensile testing machine to gain mechanical parameters of spray-applied cellulose insulation layers. The involved parameters were shear stress, tensile resistance (in as well as normal to layer direction) compression strength and thermal conductivity. The results indicated that the tensile resistance of binder reinforced spray-applied cellulose insulation can achieve and even overtop threshold values required for mineral-wool insulation boards (MW-PT). If a more homogeneous mixture between binding and cellulose can be achieved the properties may even be increased distinctly. Concerning the hygro-thermal performance of the system further research work will be done in a following project.