We are in the winter period and we want to emphasize the importance of masonry work in cold weather and also highlight the consequences of poor implementation conditions. The quality of the work depends on two things: 1 - The protection of the masonry Protect the masonry against rain and snow for 48 hours and maintain the temperature of the masonry above 0 degrees for 48 hours using an enclosure and an auxiliary heater. 2 – The temperature of the constituents of the mortar Heat the sand and/or the water between 20 degrees and 70 degrees. Diffuse heat to the front and back of the facing and at the time of installation, the masonry units must be at a temperature of at least 7 degrees Celsius.