Thin-joint masonry: bed reinforcement

[SuperPav]

Hi all, we're about to start going up with Celcon blocks (630x215) on thin joint mortar.

 

Where bed reinforcement is specified (every other course/above windows etc.) I'm struggling to get my head round which product is required. The H&H manual doesn't help much, neither does the airtec one, mentioning "a proprietary fibreglass mesh may be used" without any further info or offering any of their own products.

 

Presumably the long straight steel ones are no-go as they are over 3mm in height, so won't work with thin joint?

 

Is it a case of just getting some 100mm fibreglass tape as you'd use for joining cement boards when tiling? Presumably it needs to be alkali resistant if used with thin joint mortar on concrete blocks?

 

If anybody can direct me to a product, that'd be great!

[Mr Punter]

It may be worth giving Celcon a call.  I have found that these sorts of blocks can be more prone to cracking than aggregate blocks so I would want some proper assurance, as will your engineer and warranty provider.

[nod]

2 hours ago, Mr Punter said:

It may be worth giving Celcon a call.  I have found that these sorts of blocks can be more prone to cracking than aggregate blocks so I would want some proper assurance, as will your engineer and warranty provider.

Good advise 

Throw it to your SE

[SuperPav]

OK so I can now see why nobody uses thin-joint here! To be clear this is for finish cracking reduction and not "structural" as such. The builders (who have built lots of one-off houses locally with thin joint) said they don't bother with the tape at all as they dry-line normally and the settlement cracking isn't an issue, and building inspector isn't fussed either. So I'm doing this primarily for my own peace of mind and trying to I guess overengineer to remove any potential for bad cracking.

 

Hopefully this helps others too in the future:

H&H have provided me with a product recommendation (Bekaert CCR Compact A). I started looking for this and basically failed to find anyone who supplies it (and even the Compact C and Compact I is hard to find). Then 30 minutes later they emailed me to say that was the wrong product, and actually what i need is Bekaert Bricktor CCR (stainless steel) and this should be used if a wet finish is installed. This stuff seems COMPLETLEY unobtainable.

 

They've also said that fibreglass tape can be used to limit cracking for dry finishes, any product/manufacturer, subject to it being suitable in this installation. Good luck with that. All the alkali-resistant tapes are primarily for cement board installation and obviously not tested or certified for wall reinforcement, even though they would most likely be 100% fine and H&H's own youtube video from 10 years ago shows them just using generic fibreglass mesh.

 

Bekaert themselves have flat stamped Brickforce Stainless reinforcement marked as suitable for thin joint. I can get hold of this and it's relatively reasonably priced but total height is 2.7mm which to me is still too much for a 2-3mm nominal bed.

 

I've now got hold of a local supplier who specialise in Thin-Joint installation supplies, so will see what they can offer....

 

I'll post back once I've sorted it!

[gravelrash]

what about render mesh...big rolls but easy to cut, and probably a darn site cheaper

[phatboy]

I'd like to hear the outcome too.... our project is currently with the engineer, but hoping to use either Celcon Plus / Jumbo, or Durox Supablocks with thin joint, so will need to do the same thing.

 

Our block layer is a trusted eastern European guy, who laid it there for years before coming to the UK... he thinks we are backward for using concrete blocks and 10mm mortar beds.....