Hi and thank you for using Just Answer;I'm sorry but I don't quite understand your question 100%. If you can take the time to answer some questions, it'll help me understand what you are dealing with.When was this porch extension built? Is it attached permanently to your home? When it rains, you mentioned "the wrong direction" Does that mean that the run off is washing back towards your house instead of towards the yard? What kind of damage are you experiencing now? Where they there prior to you adding to the porch? ThanksGary
Porch was built some 40 years ago at the same time as the house. It originally had a flat roof but this was replaced with a single pitched tiled roof some 15 years ago.
Water enters the porch when prolonged heavy rain, driven by prevailing westerly wind strikes the building face.
I have extended the flashing and sprayed the house (brick) face with silicone waterproofer.
My assumption is that after prolonged rain the external facing bricks get soaked with water which then runs down the back (internal) face and in the absence of a cavity tray the water penetrates the interior of the porch.
Has recently become a more common, has been particularly a problem over the past two years - the prevailing wind direction seems to have shifted over this period!
Cement grout (mortar) is fine, seems was mixed with a good cement content and remains hard. The brick is good quality.
No subsidence or stress cracks inside or out.
Just to reiterate, in case we are going off at a tangent - what I was seeking was if information as to whether there is any propriety system on the market that enables the installation of a cavity break or tray (possibly a chemical injection system?) without the need to start breaking out courses of brickwork.
I would mention that I am a retired Civil Engineer and have a grasp of most commonplace fabric problems related to buildings.
Thanks for your assistance - looks like I will have to bite the bullet (or move!)