How to fix crack on exterior render?

[apm2011]

there are cracks under windows and on top of the flashing over bricks. What could cause this and should the gap over the flashing be sealed? How can I repair the cracks?

[EricL]

Hello @apm2011 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about fixing a crack on your render.

I suggest having a quick look at this discussion - How to fix cracks in exterior render? by @ashsew. I recommended cleaning the gaps with a wire brush kit to remove any dust and debris that might be lingering in the crack. I suggested using Poly 500g Exterior Brick and Render Masonry to fill the cracks and using either a dry sponge or toothbrush to stipple the surface of the filler to match your walls finish. Please note that it will be necessary to paint the patched area as they will not be the same colour as your wall.

There must be some form of movement or settling that is occurring along your wall. I would hazard a guess that the movement or settling is very minimal and could be the cause of the render cracking.

Here is a link to our best advice: How do you fix cracks in rendered blueboard?

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

If you have any other questions we can help with, please let us know.

Eric

[Dave-1]

Good Evening @apm2011 

I agree with @EricL on the probable cause of cracks appearing and the product to use to fill it if you want to. I would maybe keep an eye on it and see if it expands more so. Lots of places have small cracks appear as the ground settles. I try not to stress about them (generally I fail lol) But if you watch over them for a month or two you may even notice them closing a little. If they get bigger then I would use that fill.

Dave

[Nailbag]

Hi @apm2011 

The horizontal line will be the back side of the flashing (see image below). Its not uncommon to get crack and other surface imperfections arising as houses settle, which will vary depend on quality of build. 

How @EricL has described as going about repair is exactly what I would be suggesting. However If this is a new build and being the first owner, you maybe eligible to have the work done under the builders insurance. As a second owner you may also be eligible if it's within the timeframe. is this an option?

If not and you are going to repair the cracks yourself, be aware the compound suggested goes on dark grey, so it will be very noticeable. So 1. make sure you feather out the compound as it's applied. 2. Then after painting over with a suitable primer you will need a small tin of exterior paint matching the render colour.

If you don't know the colour, consider taking out a small chip from a concealed area of the wall to the Paint shop to get it matched.

Regards, Nailbag