Damp patch on EXTERIOR cavity wall

[trickymicky69]

Thank you for that info

Seems weird the patch is still growing, even after dry weather

Also I don't know if its relevant but my roof is just tiled, no felt

 

[jeds]

Something in the cavity may be absorbing water and then continuing to release it for a few days afterwards. Masonry or maybe insulation? Is the roof gabled or hipped? If it's gabled water may be getting into the grouting or maybe the ridge and running down the cloaking board.

 

[trickymicky69]

Its a gabled roof, no insulation in the cavity

Hope that helps

 

[trickymicky69]

I have borrowed an inspection camera for this afternoon so will remove a brick and have a look around

My "hopper" that takes my rainwater away (and bath water) goes into a gully through the grid and the bottom of the drainpipe finishes in the water rather than above it

Would it make any difference?

 

[trickymicky69]

So on further inspection the cavity seems dry

Strange that the exterior bricks look damp