Concrete tile was created for Southern California and Mediterranean coasts. It is excellent at reflecting strong sunlight and occasionally shedding rain. Surrey, British Columbia, offers the complete opposite: 1,400 mm of yearly rainfall distributed over 169 wet days, winter humidity that hardly ever falls below 81%, and around 25 to 35 freeze-thaw cycles annually, with temperatures frequently falling below zero between November and March.
Concrete is naturally porous. Each tile can absorb moisture during extended rainy seasons. Over time, repeated freeze-thaw cycles create tiny cracks that continue to expand. Eventually, the roof becomes fragile enough that even basic repair work can damage surrounding tiles.
However, the actual point of failure is not the tiles. It is the underlayment. The lifespan of conventional felt paper underneath concrete tile is only 12 to 20 years. Organic cardboard underlayment or thin polyethylene sheeting, which deteriorates even more quickly, were common in Lower Mainland tile installations from the 1990s. The waterproofing layer underneath the tiles breaks halfway through their 50-year theoretical lifespan. Water has been moving through a failed underlayment for months by the time you notice a ceiling stain. Almost every tile roof evaluation we perform throughout Surrey reveals this.
