Crazing finedown

[karrrl]

i have done a little job doing smooth render top coat 5 1 1 and i have had a lot of crazing with a few small cracks .
Any ideas whats causing them wall was wet before application mix as above render seems to be solid enough tho i thought i may be getting on it too early
Any help would be great the

 

[scotsplasterer]

what ratio was scratch coat, sand cement cracks thats the main problem with it, sounds like a suction issue, did it take up fast, how thick was your top coat,theirs loads of things that cause crazing. tell us a bit more, i.e whats the substrate ? getting on it to ealy were you floating it up when it was still wet, not that it would cause crazing

 

[karrrl]

scratch 4 1 with wproofer over block top coat about 6-8 mil at most will over floating it make it blow also its still sound on the wall but shows the cracks more when wet
thanks for the reply

 

[goody]

been using bagged renders for a while now and hearing talk about crazing etc sort of makes you think how far things have come but how little they've moved on

 

[scotsplasterer]

na over floating just leaves it sandy as hell, did it sook the top coat when you put it on, what like was it to float, ratios sound ok, how much w proofer did u use, as i sais mate sand cements bad for the cracks and crazing, try use a polymere based render in future, their alot better, powerwall do 1 called smoothband, i use it all the time and find it alot better than sand cement.

 

[plastering2]

i have done a little job doing smooth render top coat 5 1 1 and i have had a lot of crazing with a few small cracks .
Any ideas whats causing them wall was wet before application mix as above render seems to be solid enough tho i thought i may be getting on it too early
Any help would be great the

Hi mate are you using any feb/plastersizer in your mix? if so then the feb and lime does the same job and means your mix will be holding too much water. I came across the same problem a while ago on a couple of jobs so i stopped using lime and just used a 5 1 mix and since then had no problems. Hope this helps!