hi, I am looking at trying to fill this gap behind the tiles in the bathroom, what should I use 🙂
Welcome to the Bunnings Workshop community @m_ee_e. It's fabulous to have you join us, and many thanks for your question about filling a grout gap.You could fill this area with grout, or alternatively, since there's been a bit of movement that has caused the grout to crack, you can use silicone, which is flexible. Using silicone will prevent cracking issues in the future.
Here's a helpful guide: How to apply silicone sealant.Please let me know if you have any questions.Mitchell