Cracks in render

[RAZR63]

Just dug out deep render cracks in my friends Villa. Now time to repair it. What is the best product/material to fill it with?

[TAC]

6mm diameter helical bars in 304 grade austenitic stainless steel and Polyester Anchoring Resin

[Keithcaley]

Just use any old pre-mixed filler (macun).

If the wall is moving, it will come back anyway - unless you go the whole hog with TAC's suggestion.

[Medjoul1]

Sound advice Keith, if the there is movement the stresses will to be too great and it will crack in another place. Use the cheapest filler and keep an eye on it. I have to do the same crackes every year and have been doing for fifteen years. So have my neighbours.

[Geoff1131]

Many years ago now ( seems like someone else's life ) i worked on a large housing contract in Saudi Arabia, where the construction process was similar to here. Concrete slab with concrete pillars and block infill. They had problems with small settlement cracks on the exterior walls which apparently was due to the different expansion rates between the concrete structure and the infill. I am a plumber by trade not a builder, just saying what they found there. They ground out the cracks and used a product called ' dymeric mastic ' not sure of the spelling. And this worked like a dream. It sticks to both sides of the crack but does not go hard, stays flexible and continues to move . It can be painted over and i saw cracks and even expansion joints filled with this stuff and seemed to work well. Not sure if it is available here but maybe worth asking?

[jimm]

There is a flexible filler available in the TRNC but I have forgotten what it is called, I have used it and it has stopped my cracks coming back, Izzies in Karsiyaka stocks it.

[13roman58]

There is a flexible filler available in the TRNC but I have forgotten what it is called, I have used it and it has stopped my cracks coming back, Izzies in Karsiyaka stocks it.

It's called 'Cratex' made by Kale.
Blue tub for large cracks, pink for thinner cracks,

[PapaBravo]

Thank you 13roman58.

[RAZR63]

thanks everyone for all your responses very useful.

[jofra]

"It's called 'Cratex' made by Kale."
.... So (hopefully) available at various places - due to two previous experiences with Izzies, I will no longer touch him even with a bargepole....

[Medjoul1]

Jofra, I'm with you on that subject. I've used Cratex many times over the years and still have to repeat the process anually. We get the 'shrinkage' cracks mainly around the corners of the windows as Geoff 1131has said but the larger cracks caused by movement of the building we just have to live with. Its just down to poor construction.