Hi team; whats your the best / easiest product to fill these external gaps cracks before repainting some external walls ? Paint will be Dulux weather shield or similar
Hi @PscottDIY,
Our experienced community member @Nailbag has written an article on How to repair a rendered wall which provides solutions to your issues.
For the crack in the first image, you'll want to tidy up the crack, removing any loose material, then applying https://www.bunnings.com.au/polyfilla-500g-exterior-brick-and-render-masonry_p1210565 to fill the crack.
To tidy up the crack, somewhat counterintuitively, I would start by widening it a bit so that it forms more of a v-groove that can then be filled more easily. This can be done with a hammer and a cold chisel. Angle the chisel in towards the crack and chip away the sharp edges by tapping it with a hammer. Once widened, tidy things up with a wire brush, ensuring all loose material has been removed.
For the other gaps where the render meets the ground, you'll want to remove any loose material and tidy it up using the same method of striking with a chisel then clean up with your wire brush. When prepared use a flexible filler such as the Sikaflex 11FC that Nailbag mentioned in his article to fill the gaps. It is essential that you use a flexible filler in these locations as horizontal and vertical surfaces move in different ways, so the flexibility will prevent further cracking. Check out https://www.bunnings.com.au/diy-advice/diy-skills/tiling/how-to-silicone-a-gap for some guidance on applying the Sikaflex. The situation is different but the technique is much the same.
Once the render and Sikaflex have cured, tape off any areas where you don't want paint then apply your exterior grade paint to finish up the repair.
Let me know what you think and if you have further questions, please don't hesitate to ask.
Jacob
