Botched garden wall

forgotmyname

Moisture from behind the wall.  Probably youtube videos covering it in detail.

Mortar absorbs moisture and it freezes and breaks up or in a constant state of dampness,  you often
find it in retaining walls where the property is lower down the hill.

Water seeps through the ground and the lower down the hill you are the worse it gets, especially when someone puts
up a retaining wall that creates its own pond behind it.

stuart45

Bindone2 said: hence why I also say is there a way of testing to say otherwise. 

You'd need to look online for companies that would test it. To find out the mix ratios they dry it out in an oven, weigh it, soak it in acid to get rid of the cement and lime, dry it again and weigh it again.
They can then work out the volume mix from that. It's normally done on large sites when a number of houses have been affected.