Should I remove expanding foam between house and driveway?

Sashimi

Hi, we recently went in store as the grey foam between our house and our patio / driveway was deteriorated and weeds and insects were accumulating.

We were recommended the polyfilla expanding foam and have applied this all around.

After the fact, we researched online and found the right way was to replace the abelflex and then apply sika sealant over the top for flexibility with movement and waterproofing.

Is it necessary to fix our mistake or is the polyfilla expanding foam still a suitable option?

JacobZ

Hi @Sashimi,

Welcome to the Bunnings Workshop community, it is fantastic to have you with us.

While the Polyfilla Expanding Foam is not typically used for this purpose, fundamentally, it should act in the same way as Abelflex, in that it will fill the gap while still allowing for slight expansion of the concrete.

Ultimately, it is not the standard method of filling expansion gaps in concrete, but it shouldn't cause you issues. If it doesn't look too bad, you could probably just cut it back so that it is just below the surface of the gap, and seal over the top with Sikaflex 11FC Purform.

If you'd like things to be done in the standard way, it is probably worth removing and replacing with Abelflex before sealing over the top with Sikaflex 11FC Purform.

Check out How to fill a joint in a concrete slab for an example of this process.

Let me know what you think.

Jacob