How to best clean unsealed kitchen grout so that it can be sealed and/or regrouting later

Question

I have a problem with unsealed kitchen grout on ceramic tile as it has never been sealed and dirt has allowed to set in. In addition it probably needs regrouted later (pictures below) but sealing it could prevent damage and allow it to be addressed in the future when there is more time.

The issues is I don't know what chemicals I can or should not use nor how to clean unsealed tile without causing more damage. I would normally use professional strength products but I'm afraid it will damage the tile and/or grout as I'm inexperienced with cleaning unsealed grout.

The picture below provides below give indication of the status of my grout. I would appreciate any advice.

Another thing I would appreciate from an expert is assurance that grout is porous and that some stains will "soak in" and not come out despite how much of cleans them thus eventually requiring more reason to regrout much later. I need this "assurance" to accept it and move one.

I'm hoping professional tile layers will answer but all opinions and advice are appreciated at this point. I want to thank anyone who takes time to respond. If possible could someone confirm if it will need regrouted later?

Pictures can be found at Imgur

Answer 1

I have done this many times. Yes, I am an electrician, but I grew up in a family business doing everything and working for a electrical contractor that paid me more as an apprentice.

If the grout is solid (it looks good) I would use a very weak solution of muriatic acid and water, maybe a cup of MA to a gallon of water to clean it out. After that, triple rinse with with clear water, and after it has dried it can be sealed.

I do see a few minor voids but the weak acid solution will clean out the area. It may take a wet vac to pull the moisture between rinses but once done it will be clean and a fresh surface to seal. If it looks uneven a 2nd treatment with maybe a stronger muriatic acid/water may be needed.

I had to do this on my mom's new countertops a while after dad passed many years ago. I have resealed the counter tops several times over the years and they still look great after more than 35 years. Please remember always add acid to water (to prevent splashing of full-strength acid) and use gloves. Muriatic can be purchased at many big box stores and pool supply outlets.

Answer 2

I have not personally done this but I know they make an attachment for oscillating tools that help clean grout. It seems that this particular product has mixed reviews, but perhaps this will help you out a little!

Answer 3

Steam is the best for that; it removes all dirt and stains most of the time, and leaves no residues behind.

Answer 4

You don't need crazy chemicals. If it isn't coming clean with a hard bristled brush and whatever household cleanser you prefer (tilex? bar keepers friend? ajax?) then try something like Clean Team Scum Bum.

But yes, grout is porous and it is possible to stain it. Usually a stiff bristle brush and some cleanser will get it clean.

Note: as noted in the comments, "crazy chemicals" is not particularly specific. I mostly meant that in my experience, you don't need to find a specialized "professional strength product."