OT: Taking care of bathroom marble and grout
 

The house we bought had a bathroom update done sometime in the past 20 years (I think...)

The floor has large marble tiles and the shower has small tiles. The grout is dingy in places and the tiling darkens a bit after getting wet.

What should I do, if anything, to clean the grout lines and seal the marble against absorbing water?

Is this a DIY or should I outsource. Googling suggests a lot of individual grout line cleaning, brushing, etc...

Thanks!

If it is really marble you have to be careful as it can be damaged by certain chemicals. It is not as tough as granite or quartz. We installed marble countertops in our two bathrooms years ago. They are beautiful and still look nice but we have been careful not to spill anything but water on them.
There are products to clean and seal it but you have to reapply them periodically. The grout seems problematic to me.

Correct about the marble. Keep the pH of whatever cleaning solution that you use >pH ~5. Also, if you're doing an entire regrouting on a large area, hire a pro. It's not that hard to do DIY, but a pro will knock it out lickety split....

Well, since you brought it up, I have the same question—a few places where the grout has failed.




And just for good measure on this perfect spring day here, a pic of the bike, ready to go. House stuff can wait.

I just redid a fair amount of a walkin shower grout. Bought a vibratory multitool for the corners etc but it was slow so ended up being very careful with a angle grinder and diamond tile blade. Took a couple hours to remove most of the grout in the bad areas-above waterline was ok- and clean up the dusty mess. Regrouted with Mapei (cycling content!) with a anti mildew additive in a matching color.
Once the grout is to the point where it is repeatedly staining, or failed, this is best solution.

I just regrouted two bathrooms and have suggestions, advice, warnings, whatever you want to call them.
I did that after trying several internet, home, professional fixes. None did a thing to clean the grout.
1) It's dirtier than you can imagine to regrout. The dust gets everywhere
2) Wear the breathing protection all the time during removal. See above
3) If you have more than one bathroom you want to do, DO ONE, THEN THE OTHER. Or, read the instructions ALL THE WAY TO THE END and don't be like me who read the grout sets in 24 hours and thought easy, I'll start the other while I wait. It SETS in one day, needs 3 days to bear moisture, and if you seal it, 3 MORE days.
4) DO NOT pour water with grout dust/droppings down your drains. Just don't. Out in the yard, on a pile of leaves. Let the water dry up, scoop up the leaves, toss them.
You can do it all by hand, I did and it wasn't hard. Just took longer, probably.
5) After, get used to squeegeeing the tile after every shower/bath. Makes a big difference.