How to fix grout gaps and cracks?

[Msteain]

Hi all, first time poster and DIY beginner. 

Our showers are in need of a tidy up, and I am getting prepped to seal the grout, and removing then re-apply silicon. However I've noticed that our wall grout has cracks and imperfections, and our floor grout has some areas that dont appear fully filled.

I've been considering using a dunlop grout bottle to fill the gaps/top up the grout before sealing everything but I was looking to see if I'm on the right track? 

Any suggestions would be appreciated.

  

[JacobZ]

Hi @Msteain,

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

You typically need a bit more depth so that the new grout can bond to a wider surface area. If you were to just top up the existing grout, it would be fairly weak and susceptible to further cracking.

My suggestion would be to scrape out the cracked and low sections with a Grout Saw, then apply your Dunlop Ready-To-Go Coloured Grout to the deepened grout lines. 

With the added depth you have created, the new grout will have a much stronger hold than it would if you were to just top up over the old grout.

Once it has dried, you can seal it with a grout sealer to finish off your grout rejuvenation project.

Let me know what you think.

Jacob

[Msteain]

Thanks Jacob,

I'll give it a go!

[Msteain]

Hey @JacobZ 

I need to pause the work during the work week, and I wanted your opinikn on leaving the shower for a few days. There is a 3mm deep, 0.5mm high gap between the wall and floor tiles now. Should I put anything under the tile with removed silicon to support the wall?

  

[JacobZ]

Hi @Msteain,

The silicone is not actually supporting any weight, so there is no need to put anything in there to support the tiles.

I would avoid using the shower until the silicone can be replaced, as water can get in under the tiles, which can cause mould to grow underneath them.

As long as it is kept dry, you can leave it without any worries.

Jacob

[Msteain]

Perfect,

Thank you!