Exterior of the brick and plaster water considering you had them you must first impervious to water. There are several varieties of these;
  1-waterproof plasters can be used
  2-Sıvalarınızın is also used for the purpose of the thermal insulation on the sheathing if you make a layer of the system which is used on plasters in waterproof against water, you protect your brick walls and plaster.

Sıvalarınızda that cracks, fix with mortar, plaster water resistance into your Crystal producing still exterior lock your water. Waterproof exterior coatings to shield them from outside intrusion helps in maintaining your building against water.