Hi im looking fo ways to fix this what type of concrete do i use for foundation repair. Its only in this spot not sure how long it has been like this. There is also a split that looks like foam has been placed in it. rest of slab looks in fair condition
Hi @mills28,
The vertical split with the foam pushed inside is a control joint. It is an intentional joint in the wall that allows for movement, so I wouldn’t fill that section with concrete. If the foam is loose or untidy, you can replace it with some new foam, such as this https://www.bunnings.com.au/sika-10-x-100mm-x-25m-abelflex-expansion-joint-filler-foam_p1060067 , then cover it with some https://www.bunnings.com.au/sika-600ml-concrete-grey-sikaflex-11fc-purform_p0628966 . Have a look at How to fill a join in a concrete slab for some guidance. The application is slightly different, but the function, installation process and materials are much the same.
Assuming you’re referring to the damaged concrete at the base of the wall -
- you should be fine to tidy that section up if the surrounding concrete is still sound. Chip away any loose or crumbly material, clean out the dust, then apply a bonding agent such as BondCrete. To help the patch key in, you can drive a few masonry screws into the solid concrete, so they sit partly exposed, then pack the area with a standard concrete mix mixed to a relatively dry consistency. A piece of timber can then be placed over the patch held in place with a couple of heavy items such as bricks or pots, as a simple formwork to hold the concrete in place while it cures.
Just make sure the concrete does not bridge that black plastic that sits between the top of the slab and the first course of bricks, as this is your dampcourse and if it is bridged with concrete, it can allow moisture to rise through the bricks, which will cause issues down the track.
Let me know what you think and if you have further questions, please don't hesitate to ask.
Jacob
Thanks jacob i will try that soon
