when to apply (4 answers) we need to seal one side of our house as the bricks are very porous, could we do it now i.e. january. Or when is the best time to do it?? Thanks Answer This A Answers As long as the wall isn't wet, you can apply this anytime of year Refer to the application guide displayed on the tin but you must be sure to have any damage to your pointing/bricks treated firstly and check you have sufficient overhang from roof. Having airbricks fitted if not already will also be beneficial for you. Refer to the application guide displayed on the tin but you must be sure to have any damage to your pointing/bricks treated firstly and check you have sufficient overhang from roof. Having airbricks fitted if not already will also be beneficial for you. Refer to the application guide displayed on the tin but you must be sure to have any damage to your pointing/bricks treated firstly and check you have sufficient overhang from roof. Having airbricks fitted if not already will also be beneficial for you.