How to remove grout with narrow gap between tiles?

justdiy01

Hi,

The grout gaps are too narrow for me to remove the existing grout using my grout rake tool from Bunnings. Because of this, I was considering applying new grout over the existing grout, particularly in the shower corners where the gaps are thinner than a blade.

What would be the best approach in this situation? I understand that applying new grout over old grout is generally not recommended, but I am unable to remove it due to the narrow spacing.

Additionally, regarding the grout surrounding the shower drain: I’m aware there is a waterproof membrane underneath, and I’m concerned about potentially damaging it in areas where the gaps allow some grout removal. Do you have any advice on how to handle this safely?

Thank you kindly for your guidance.

JacobZ

Hi @justdiy01,

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

In this situation, where the grout line is too narrow for your grout removal tool, my suggestion is to use a utility knife instead, ensuring you wear gloves and long protective clothing while doing so. It will blunt the blade fairly quickly, but it will break up the grout enough that you can remove it with a vacuum cleaner. Having done it myself, it can be a bit tough going, but trust me, it will work; just be careful not to plunge the knife too deep.

The key to not damaging the waterproofing membrane is removing small amounts of grout at a time; do not try to scrape everything out in one go. Take your time and work your way down over the course of many passes. Also, remember that you do not need to scrape out absolutely all of the existing grout; you just need to remove any loose material and provide enough depth for the new grout to bond sufficiently with the surface around it. A depth of around 3-5mm will usually suffice, but it is worth checking the packaging of your specific grout to see if there are recommendations.

If there is anywhere that you can see the tile edge, knowing their thickness will also be a great help. If, for example, the tiles are 10mm thick, then you can place a mark on your grout tool or utility knife 10mm back from the tip to act as a depth gauge to ensure you do not go too deep.

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

Jacob