1820 Georgian house that has cement render.

[cozzie81]

I've got one room that we are renovating so may be I'll get the chisel out & remove the gypsum from that wall & see what's happening underneath.

 

[IHateDamp]

No I've never seen that before, looks interesting.

As I said I've no signs of damp that I can see or touch so far. Also my house is a 3 storey over basement, would removing a small section of cement render make that much of a difference to the overall fabric?

I don't know if it would. If it ain't broke comes to mind

I would be a tiny bit curious that if you removed a bit of render at the base, if the stonework was damp behind it or not, just because I'm nosey.

 

[cozzie81]

Yes, if you went the IWI route you'd need to take off the gypsum plaster (for us it was easy peasy as the gypsum plaster was a skim on top of the original lime) and then go from there.The Wood Fibre for us (we've gone for 80mm) has made a tremendous difference. We've had the ability to do it one room at a time which helps. If you can do it properly internally at least that gives one route for the wall to stay dry.

There's no way I'd spend that kind of money doing render. Fundamentally it's not a complex job and I fail to believe there aren't cheaper ways of getting it done. But if there aren't, it's hard to see how you justiy the cost given you're saying you don't have evidence of it causing problems.

Perhaps consider doing one or two rooms internally with wood fibre insulation first, learn from it, and see where that takes you.

So I removed a tiny piece of the plaster in one bedroom & placed it in a cup of vinegar, there was a few bubbles & it's definitely making a fizzing sound when I brought it up to my ear.

Could be wishful thinking on my part but it's definitely not as smooth as cement render either, but maybe it was just a poor job.