Hi there
Any ideas on how to fix this
Hi @kikop,
Welcome to the Bunnings Workshop community, it is fantastic to have you with us.
The process will involve filling the gap with a mortar compound, to just below the surface, allowing it to dry and fully cure, then rendering it and painting to match the wall.
The first thing I'd suggest is you reach out to the plumber to double check if the pipe needs to be wrapped with insulation, which is referred to as pipe lagging. You can see there was pipe insulation in place, so I'd say it is needed, in which case you would use the pipe insulation that matches the diameter of your pipe.
Then you would clean out any loose material, wet the inside of the opening, then use a deep fill structural mortar, such as https://www.bunnings.com.au/sika-20kg-sika-monotop-352nfg-structural-repair-mortar_p0760433 to fill the hole to about 5mm below the surface of the render. Mix your mortar as per the instructions then press it into the opening using a brick trowel. Once filled, allow the mortar to cure overnight before proceeding.
You can then apply https://www.bunnings.com.au/products/building-hardware/cement-concreting/cement-products/render over the patch, allow it to cure as per the instructions, then paint it to match the surrounding area.
Check out https://www.bunnings.com.au/diy-advice/home-improvement/walls/how-to-render for some guidance on the rendering process.
Let me know if you have any further questions.
Jacob
