Polymer modified cement mortar has been used for the repair and waterproofing of concrete structures extensively. In the work reported here, mortars with different types of commercially-available water proofing materials have been subjected to weathering consisting of exposure to UV light and wetting-drying cycles. The effect of the weathering was assessed on changes in water permeability, bond and flexural strength, all of which are critical for long term performance. The results show that there is significant increase in the strength parameters and a marginal decrease in the bond strength and water impermeability for polymer based water proofing materials due to the accelerated weathering. In the case of the cement mortar with a lignosulphonate based integral waterproofing material, the reduction in the properties was much more than for the other polymer based materials (i.e., latexes). © 2012 Taylor & Francis Group.