Over strong mortars and renders can crack blocks. We coated new builds that have stood water tight for months and months only recently for the blocks to crack within a week of the stuff going on.
Yeah but mono is around 5.1 or weaker, the benefits of factory blended mortars in the first place to avoid what you said happened to you above. It was a problem with krend in the past but again why was the blend incorrect in the first place.? To many wrongs don't make a right bit I will take your word for it.
They have all had problems in the past though. Parex EHI wasn't / isn't as good as the Monorex to apply, and Parex imo isn't a particularly good fit for the UK's climate without spending more money. I've seen recent Weber jobs where 7 nm blocks are shattered like glass and others are saying the same thing .
My point is that I find all material currently on the market has its quirks and it all needs looking after. Maybe we're being too anal but until I get a problem I'll stick with it.
It's not uncommon for blocks to crack before render same as it's not uncommon for them to crack straight after. I reckon that some renders can push blocks already under stress over the edge.
Just noticed having a Google about, K Rend have an automated spec writer on their website where one coat spec onto block is readily offered if you put the right details in.
Ehi is a mare but its right spec for insulation and boarded construction.
You already said you had problems with it tho not splitting open as much as it used to ? That's why I asked why use it you don't have to do that.
Slower setters are better overall for reduction in cracking risk I don't think the climate is an issue. As long as you stay away in Jan and Feb.
Granicem is lovely gear and very slow. Easy scrapes next morning never had a crack in that. They also have a granicem UL specific for house builders who insist on using lightweight's.
Have you tried it ? Sprays like cream
I'm not a spec changer, if somebody wants something that's what they get. There's a good chance trying to change spec will only earn you a nod, wink and thanks for your time as there's always someone who will put on what the customer wants. We'll even hand apply FT if that's what we are asked for, even that is niceish if you mix it enough.
Not used the Granicem personally but I've heard it's nice stuff.
The K1 creams up lovely and only medium settings on the pump and is nice to spat. We got a couple of small splits on a couple of jobs at high level when windy which disappeared when we rubbed some snot in before scraping but the guy who flogged us the pump mentioned misting the walls down before and after and not had any since. Do that for everything now, helps keep job nice and supple and makes scraping easier to see.