effervescence and spalling

[nickso]

Hi folks.

I have effervescence/blooming started on 3 external walls. All 3 are garden boundaries shared by neighbours and are 25 years old. We've only been here 2 years but it wasn't doing it last year so who knows why it's started now. I'm wondering if maybe it's because the top of the walls is not a coping stone but a course of bricks on top of roofing slate type material, you know the sort of thing. This top course is broken/spalling probably from frost. Some of the lower brickwork in the walls are also starting to spall and I want to stop it quickly.

I've read water ingress from above is the likely culprit, does that sound right?

Does it sound reasonable in the short term, while potentially no one wants to come round and sort it with proper coping on top cos of Covid, to brush off as much of the salts as possible and seal everything with the likes of Thompsons Water Seal to prevent any more water getting in from above? Is that going to be a waste of time and money?

Cheers.

Nick.

 

[noseall]

who knows why it's started now.

It is now efflorescence season. It's everywhere you look.
However, this year is different in that this years' blooms have followed 3 severe driving rain storms.

 

[JohnD]

Is that going to be a waste of time and money?

yes

it'll weather away.

 

[^woody^]

it'll weather away.

In about 200 years

 

[JohnD]

nah.

 

[nickso]

A nice concise response with real suggestions of solutions to the problem. Thanks chaps.