Wet patch/leak on external wall by new porch

[RMB]

I seek some advice.
We had an extension including back porch built in June. 5 weeks ago (early October) after days of rain we noticed a small wet patch on the red bricks (on pic 1.marked with a star) and pebbledash. This gradually grew larger and with daily rain has become permanent.Then it started penetrating through to the inside wall of the porch
There is a downpipe from the upper roof to the porch and this was facing inwards towards where the porch joins the wall I thought the rainwater might have flowed beneath the flashing.I turned this the opposite way and the builders sealed alongside the flashing. As a temporary bodge I have placed a piece of guttering beneath the downpipe to ensure the flow of water is well away from the side where the wet patch is.
Can anyone identify the source of the wet patch?

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• RMB
• 10 Nov 2013
• 1

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• RMB
• 10 Nov 2013
• 1

Untitled

• RMB
• 10 Nov 2013
• 1

Untitled

• RMB
• 10 Nov 2013
• 1

 

[Burnerman]

Maybe the roof has a slight slope to the left, and the water is cascading over the flashing?
Next time its raining, see what happens, and keep an eye on water falling from the main roof above.
John

 

[Alastairreid]

Looks like the gutter above is tipping water onto the porch.

 

[catlad]

There is a lot going on for a small roof, tipping water on to a roof that is already under pitched is looking for trouble.

 

[RMB]

8) Thanks for your comments so far - I have looked for rainwater dripping from guttering and roof above during rain but have been unable to see any. I will check the angle of the porch roof and continue observing during rainfall. I agree there is a lot of water flowing onto a small roof.

 

[noseall]

How you gonna go on when you have driving rain, cover your house in polythene?