Has this wall been dashed all its life?

[cjard]

The side walls of my building are pebble dash over random stone with line mortar. Inside is engineering brick, EGW bonded to the stone every 3 courses, with a rubble fill. The building was built in 1926 and has a coursed stone (non dashed) front wall. At the corners are castellated large blocks of stone that tie the corner, and they're flush with the pebbledash. I was under the impression that it had been dashed all its life and the render was a vital part of the weatherproofing of the wall. A builder friend disagreed, saying that pebble dashing with Portland cement mortar hadn't been invented in 1926.

The question comes about because I'm wondering whether it'd be a good idea to strip the pebble dashing off back to the original stone, or not. It'd certainly be prettier, but I don't want to cause a problem with moisture ingress leading to problems for the outer skin; it's quite an exposed location

 

[vinn]

You have a lime mortar in the stone joins & the brick beds, and a sand & cement render for the dash.
The render was a retro installation to prevent penetrating moisture.
So dont strip off the render leave as is, it looks to be in good condition.

If you have interior damp signs then thats a different matter.

Portland cement as we know it has been around for a couple of centuries. In many parts of the country cement replaced lime in the early part of the 20thC.