Hairline cracks in render

Status
Not open for further replies.
Rendered up a timber framed double garage about six months ago.
Wired it with EML, the one pricking up coat, one scratch coat then a rubbed up floating coat. Put fibres in the mix. The render has now developed quite a few hairline cracks all running from top to bottom, anyone got any ideas why this may of happened and what would be the best way to filll them.

Thanks in advance for any replies.
 
Thanks guys for your replies, I think I have found the reason why ! the timber frame was sheeted with building paper fixed over 12mm ply we could n't fix counter battens because we would have come out further than the roof tiles. we used 20mm screws with washers to fix the EML and even they were coming out the other side of the ply.

What does the forum think ?
 
I'd never put EML straight onto ply again. I did it once years ago at the insistence of a builder and had the same thing happen and he still wanted to do the next property the same way, I refused, battened it out and and not a crack in site. Also a lot of people I've seen fixing EML don't use tie wire to join sheets.
 
I use a breathable roofing membrane rather than building paper, dont know if it makes any difference, and like andy said we battoned it out rather than on to the ply so that the render could get a good grip on the EML
 
Timber Frames always shrink in the first 12 - 18 months, you have to build in movement control, or get advise on the expected shrinkage and allow for it.
It is now better to apply a cavity, board and render to a TF, rather than direct apply riblath or mesh and direct apply...... when the shrinkage happens the render moves and cracks (micro to start with....). Every TF is different based on shape, design, loading and roof loading!

Contact me if you want information and assistance with boarding TF projects - Various approved render system options available!

rlord@knauf.co.uk - 07918766577 - Knauf Aquapanel Exterior Cement Board
 
alright mr capital john. hows things??

Hi nicklarse very very busy at the moment, thanks guys for your replies I did think about battening it out but it was tight on the edge of the roof tiles. Never had any trouble before going over ply wish I had walked away now.
See even old dogs like me get caught out.
 
Status
Not open for further replies.
Back
Top