Regrout or grout pen?

[xfilesandicecream]

In our bathroom a section of floor tiling grout is all crumbly, I tried to replace with unibond quick fix and regrout but it recrumbled.

The actual grout is supposed to be white, but has discoloured, and so I'm wondering if I'm best to just regrout the entire floor? It's not something I've done before but we're wanting to hopefully sell our house soon and it does look terrible. Am I right in thinking white would discolour quickly and grey would look better (we have pale grey tiles). A grout pen sounds much easier but I'm wondering if the grout maybe too far gone sadly

Many thanks in advance for any advice!

If it a crumbling then I guess you have to replace. You can get grout removal tools or use a multi cutter with relevant attachment.

If it is sound, then you have to be careful of chipping the edges of the tiles when removing.

Once it's out, grouting is fairly straight forward. I used Mapei powdered stuff in last house. Mix to right consistency with water, Bash it on with a grout float, wait a little, wipe it off (in the right direction so as not to pull the grout out).

Usually match the grout colour to the tile so grey grout with grey tile sounds like a good idea.

Thank you for the advice! Daft question, when you say wipe it in the right direction, what exactly does that mean?

I also found an online video which said I needed a grout sponge and finisher - does that sound right.

My husband has a multitool so hopefully I can get the grout out!

Yeah you use the sponge once it's hardened a little to wipe off the excess and smooth the grout. Don't leave it too long cos you'll never get it off the tiles!

Don't wipe parallel to the grout as you'll drag it out. Wipe across instead