Dark/Damp patches on external brickwork

[DIYBrit]

There are some dark patches on the external brickwork at the front of my house, which I assume are caused by damp.

Some of the bricks directly beneath my bay window are dark/damp.

There are a few dark patches to the left of the front door. I assumed this was caused by direct rainfall, but the area is directly beneath a wooden door canopy.

The corner of the house, to the right of the front door, has dark patches. This area also has what looks like some kind of moss or lichen.

What could be causing these issues?

 

[^woody^]

Rain.

 

[ree]

OP,
Has CWI been blown into the main house cavity wall?
Why not post a pic of the "moss or lichen"?
The pointing needs grinding out to25mm depth, and re-pointed with a sand & NH lime 3:1 mortar mix.

 

[Koolpc]

From the pics, i dont see an issue..

 

[DIYBrit]

I dismissed this potential issue as rain for years. But what concerns me is that a few days after it has rained, there are specific areas, such as to the left of the door, which remain dark and damp. I would expect external brick work to dry consistently and evenly. Rain does come down at an angle, of course, but I doubt that area to the left of the door gets hit by rain, as it is underneath a door canopy and I never see raindrops on the door next to it.

I suspect it could have something to do with deteriorated gutters, as there is a drip from the gutter, which drips onto the postbox to the left of the front door. If this is the case, could this cause damp issues in the bricks and wall cavities?

I'm also convinced there's an issue with dampness in the bricks under the front bay window sill, as there is an area directly under the sill is always darker than the rest of the bricks. Could this be an issue with rain water leaking into the sill and into the bricks beneath?

 

[foxhole]

Clean and repair gutters , no issue unless damp areas are inside .?