How to repair sealant between concrete path and wall?

[jaynic]

Hi, I have noticed that my concrete patio has sunk slightly in one area, evident where the concrete meets the brick wall of the house. The sealant has remained attached to the wall, but come away from the patio.

Is it enough to repair the sealant, or is this something that warrents further investigation by a professional? If a cosmetic fix is appropriate, how would I go about doing that? Thanks in advance.

[JacobZ]

Hi @jaynic,

A warm welcome to the Bunnings Workshop community and thank you for your question.

It is worth noting that the settlement is right around a pipe inspection point, which could indicate that there is some minor erosion happening beneath the concrete. It is certainly worth monitoring, but at the current level, I wouldn't worry too much. It is probably just settlement.

To repair the sealant, start by cutting away the old stuff using a utility knife. Make sure you wear gloves, long protective clothing and eye protection as there is always the risk of lacerations when working with knives.

Once the old sealant has been removed, assess how wide and deep the crack is at the wall. If it is wider than about 3-5mm, it is worthwhile pushing some AbelFlex into the crack to plug the gap while still allowing the concrete to expand and contract.

After putting the AbelFlex in the crack, apply a bead of SikaFlex 11FC Purform over the top, and strike it off with a damp cloth, shaping it so that it is angled to create a fall away from the wall.

Check out How to fill a joint in a concrete slab for some further guidance.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob

[jaynic]

Thanks JacobZ, that is super helpful! Thank you for the advice.

Can you guess from the photo what Sikaflex colour would be a match? Sandstone?