New render cracking

[liam546]

I recently rendered my two chimney breasts which were solid brick with sand/cement/lime mix (5:1:1). The plasterer also used fairy liquid to help make it easier to work with.

The wall was pva'd and then the cement render put on. The plan is then to use a multi finish skim over the render. However the next day after the render the below cracks have started to appear. I know it's yet to be skimmed but will the cracks come through the skim finish too in time and are the cracks in the render normal after such a job?

Below you can see the key created but also within the key you should be able yo see the cracks I'm referring too As well

Untitled

• liam546
• 29 Sep 2014
• 1

Untitled

• liam546
• 29 Sep 2014
• 1

Untitled

• liam546
• 29 Sep 2014
• 1

 

[Alastairreid]

Shrinkage cracks caused by too much suction in the substrate.

It will be fine as long as the render has taken.

 

[liam546]

That's really pleasing to hear. Should I wait a certain number of days for render to cure and cracks to finish developing before moving ahead with skim?

 

[roughcaster]

Did he scratch coat the brick wall first and then render?

 

[liam546]

No scratch coat. Just pva'd the brick and then straight on with a render mix 5:1:1. (Sand, cement:lime) and fairy liquid in mix too.

 

[roy c]

I would use the existing wall as a scratch coat and scrim over the cracks and put another float coat on , Maybe a 6-1-1 mix...then skim it. Put a bit of plasticiser in you mix not w/proofer.......