This is a particularly common and frustrating problem and the solution lies in applying the right kind of tile cleaning product.
The first step is to assess the nature of the residue left on your tiles. Commonly this would be something called “grout haze” or fine grout residue. If so, I’d recommend using something called Microscrub. Unlike the more traditional grout or cement removers, Microscrub contains no acidic chemicals. Why is this important you might ask? Well, if you have limestone tiles, for example, the last thing you want to be applying to your tiles is anything acidic for obvious reasons. Instead, Microscrub uses a mild cream cleaner, combined with a safe abrasive cleaner which is itself derived from limestone so it won’t scratch your stone. It acts as an “exfoliating cream” for stone and will safely remove fine grout hazes and residues. The nano-technology used in the product will also work on the surface tension, allowing the cleaner to get into smaller micropores.
If you have very heavy cement or grout deposits left on your tiles, this will be far more difficult to remove. Worst case, you may have to employ a specialist floor restorer to regrind the floor. This can be done using polishing or honing compounds or diamond grinding and is a highly specialized job.
Copyright Ian Taylor and The Tile and Stone Blog.co.uk, 2013. See copyright notice above.
Hello, i have laid x3 square m of Encaustic floor tiles in a Bathroom, supplied by fired earth, i sealed them before fixing with there product, then grouted them with there flexible grout. there was some light grout residue left on the Tiles, so i cleaned them with grout residue remover and now that has left water stains on them which i cant seem to remove. I have now tried to clean them twice more but it seems to have made them worse.Please can you give some advice on cleaning them back to there original state so i can seal them once more and wax them ?
Try a mild solution of diluted Aqua Mix Phosphoric Acid
I have a stone floor that I have laid in my house . I sealed the stone with a impregnating sealer . Then grouted it with a lime stone flexable grout . I have cleaned it with a grout remover. To get rid of the haze of grout on the stone . But it is not coming off . Will the nano scub remove this .
Hi Chris, the flexible grout contains a poluymer that is designed to stick like the proverb says… amongst other things.
If not properly cleaned at the time (and this can be a bit painstaking even for pros) Even though the impregnator will have prevented the grout haze from getting deep into the stone, the polymer will have helped it stick like… to the surface, if the surface has any texture at all, then it will stick even more.
You may well need a little extra help getting this off and certainly, nanoscrub if you can get it (no worries if you cannot, Microscrub does the same job and is now avaiable from All For Stone on the top right) may well help as it may provide just enough abrasive to dislodge the grout haze.
Worst case scenario you may need a solvent to soften the polymer first
Kind regards
Ian
Hi, i recently laid some sandstone multi coloured floor tiles.Having laid them and then sealed using a colour enhancing lithofin stain stop plus, proceeded to grout them using a bal limestone flexi grout there is a massive discoluring of the surface tiles. Is there something that can be used to reduce the haze or is it irreversible now.The tiles were not left with grout on them and were cleaned straight away and washed three times but still left with a white out finish on the surface. Any feedback would be gratefully received. Thanks
Hi Darren,
I don’t think that there is any issue with the sealer, that will have helped prevent the situation from being 10 times worse. I note that you say no grout was left and it was washed three times, but I am fairly confident that it is still grout haze (i.e. thin film of residue) that you have a problem with.
Sandstone is much more porous and textured than many other popular stones and so an impregnating sealer will sit quite low in the surface (it soaks in much further than it does on other stones). Then you have a grout that is highly polymer-modified (it has synthetic latex) this grout will adhere to most things, even if they are sealed, add to this the surface porosity and texture that an impregnator will have greatly reduced, but not totally eradicated, and you have perfect conditions to trap some polymer/cement residue.
I would try a couple of things, first try to use a proprietary haze remover (based on a safe acid like phosphoric, not hydrochloric) – use it as directed, diluted with water if this does nothing them try using an abrasive scourer like Microscrub. Neither of these should harm the stone, grout or the sealer BUT TEST a small area first. There are some sandstones, (and this is worse on the semi polished/polished ones) that can react badly to mild acids).
If you get no result, then you may have to consider a solvent (to attack the polymer) treat this as the last resort as that may have some effect on the sealer also
Hope this helps
Ian
Had 2″ tiles laid in bathroom. I believe they are stone- dull finish. There was grout residue left in places and any rag I clean with gets caught in the grout and leave lint, etc. How can I clean this grout off and if not, can I seal the whole thing with something that will provide a smooth finish over all?
Hi Pat,
No point trying to seal over this. OK, first thing to try is an abrasive emulsifying pad (3M or similar) choose the white one as this will not harm you tiles, add some water and a mild abrasive cream cleaner like Nanoscrub and see if you can scrub the cement/grout off.
If that does not work you need to be more aggressive – you can use fine sand paper – start with very fine then work down until you get the results you want. You may need to go back up to a finer paper after to blend the stone finish back – depends on the finish you have to start with.
Or, use hand diamond pads, not cheap as you may need a whole set of grades to polish the tiles back to the factory finish. Another way is to use an emulsifying pad with some honing powder – again available in different grades.
Only when the grout residue is off, and the tile surface back to the finish you desire, can you seal, then try to use the same sealer that was used originally.
Hope this helps
Ian
I have some sandstone that has some grout haze. It has never been sealed. When I try to clean off the haze, the stone bleeds onto and stains the grout. Should I seal the grout first, then use nanoscrub? Will that keep the grout from staining?
Second question – I am using the same stone for an exterior patio that is covered, but will still see some rain. Should I seal the stone first before grouting? I had been planning on grouting as a lay the stones, then washing the stones, but now I’m concerned about it staining the grout. Help! Thanks.
Hi Eric,
OK, first question, the sandstone probably contains some iron-bearing mineral that gives it is a red/brown colour- this reacts with air and water (oxidize) – so basically forms rust – this is very common and it will keep happening every time the stone is cut – so a new face exposed, or when a relatively fresh face is exposed to moisture and air – so new patio slabs being washed etc – you will keep making more of this colour, some of which can in deed bleed out into the grout.
No point trying to seal the grout – you will never easily isolate the grout and seal it while not sealing the stone.
To clean the haze most people will use an acid based cleaner (often based on phosphoric acid – do not use muriatic!) and this will also help remove (or conversley, liberate from the stone) some of the ‘rust’
There are some sandstones that are sensitive to any acid cleaner and you should check that out first – does your stone etch with an acid? – if so, do not use.
If you can use it the key is to pre wet the stone (sandstone is porous and you want to fill up the stone with water so that the cleaner stays at the top). Scrub lightly and remove. That means rinse with fresh water then if you can, extract the water – either by hand with a sponge, immediately;y, or a wet vac. Don’t just blast the floor with cleaner and water then leave it to dry – the water will allow the bleed to occur plus when the water evaporates/drains through the stone, it will leave behind, or take with it into the stone, some of the dirt/haze/rust you have just spent time and energy removing – it needs to be extracted with he water while it is still in suspension.
For the second question, yes, for sure, lay the slabs, make sure they are clean and dry, then seal with your chosen sealer BEFORE grouting as this will help avoid the bleeding situation later and it will also help with the prevention of grout haze as the grout will be easier to clean off the stones in the first place.
Hope this helps
Ian
That’s great info, Ian, thanks! Only follow question is that I forgot to mention that the bleeding is happening on a vertical wall. I assume it would be the same process, only have to really be ready with the wet vac, maybe even have an assistant on hand. Any special considerations for a vertical surface?
Hi.
OK, well in some ways it is easier as you have gravity helping to take the dirty water away, but yes, same process, maybe a wet vac is less practical on a vertical surface, you can just rinse, the thing to watch is the water running off and collecting on the floor- – maybe have the wet vac to keep that under control?
hope this helps
Ian
I have recently put on a stone and glass backsplash. I think i made the mistake of not putting on a sealer before grouting. When I sponged off the grout much of it stuck in the cracks of the porous stone and i cannot remove. what can i do?
Hi Debbie,
If the stone is NOT a calcium based, or other acidic sensitive stone, (and there are no adjacent surfaces which are acid sensitive, like marble or even some granite work tops etc) then a proprietary grout residue remove based on a mild acid (not HCL/Muriatic) will be well worth a try
However in all likley hood your stone is marble or limestone or travertine or something that IS acid sensitive – if so, DO NOT USE such a product. Instead look for a microabrasive cream cleaner – you can get Nanoscrub in Canada
Hope this helps
Ian
Hi , I have just laid fired earth terracotta tiles. Thet were primed with litho loin and fire earth grout used. This was wiped straight away but there is a grout haze on the tiles. How do I get rid of this? Thanks.
It sounds like you have used some for m of sealer, which should have helped to prevent the grout from going into the tile’s surface, but there is still a grout haze left on the surface. Provided there are not acid sensitive surfaces anywhere near (like marble for example) then you will probably need a very mild acid based cleaner, just don’t use one based on Hydrochloric acid. Ask your tile store for one based on phosphoric acid, then use well diluted with a scrub pad
Hope this helps
Ian
please can you help,my builders laid my indian sandstone floor in my 100yr old cottage and destroyed it with cement which is now ingrained, we have tried all sorts, can you help
Hi Claire,
Sorry you have this issue, OK it might be a challenge but when you say you have tried all sorts, did you try an acid – based cleaner?
Normally this would be the only option for removal of cement-based contamination – however it needs care
First of all, some (not all) sandstones can themselves be susceptible to attack by acids – so you would have to ascertain if using an acid based cleaner on them , whilst it may remove or reduce the cement, whether it may permanently damage the stone also (etching it, taking away some of the colour, even causing some visible roughness etc)
You can test this in a small way in an inconspicuous area, always star with a weak solution, very dilute and AVOID brick cleaning acids as these are based on very strong hydrochloric acid and can do more harm to the stone and the grout joint.
So, try a cleaner based on a milder form of acid such as phosphoric. These are much safer, they are very quickly ‘spent’ – this means that multiple cleans may be required, as each time it takes a tiny amount away, this is BETTER as it means you are controlling the amount of damage that will also be done to the stone (if susceptible) and certainly to the grout. If the stone itself shows little issue with dilute phosphoric acid cleaners, then you may have a chance of resolving this.
use the procedure below (if testing suggests it is safe to do so):
1. pre-wet the floor – saturate the stone with water – this helps keep that cleaner where it is needed and also helps proetect the stone
2. Mix your cleaner in accordance with on bottle instructions – try it very dilute to start with and only make it stronger if it achieves nothing. Apply it to the floor
3. Leave it for a few minutes – does not need an extended dwell time – 2 to 5 minutes is enough, so do small areas at a time.
3. Scrub with a nylon scrub brush to get into the texture. (sometimes, if and only if the stone is hard enough, a wire brush can be used , or a Tinex – (a kind of artificial wire brush) but take care as the stone may be too soft for this). Ass you srcub you will expose more cement and the acid will work for a bit longer
4. pick up the solution -this is best achieved with a wet vac, but if you can’t get one, use a really good absorbent mop
5. this is one of the mos important stages RINSE WELL WITH CLEAN WATER – pick up the water
6. Inspect, the test area, if it has done cleaned the floor to your satsifaction, just repeat this process all over the floor. If it has not fully solved the problem, but it has done something (more likely) then it IS working, but will need two or more applications.
If this sounds too much for you to tackle, I would suggest contacting a friend of mine in NAAS (as you appear to be in Dublin?) you can contact him here Frank Hegarty http://www.fhi.ie – he is very experienced.
Hope this was of some help
Ian
Hi, I have just had some mosaic anti slip tiles fitted in a wet room. When the builder grouted he did a 4inch test area then did the whole floor (approx.5foot square) He then had problems taking off the grout… so left it and next day told me that it would wear off!! Tried using brick acid and nylon drill attachment, still look bad. Do you think this will work if keep cleaning with brick acid, but this is going to take days & days (slow going) OR should I just get them replaced
Hi Debbie,
I take it you have paid the guy?
He should not have left you in that situation. Sure anti slip (textured) tiles are harder to grout than standard, but he does not sound like he was really up to the job. No, the grout won’t just wear off.
It is going to need more work I’m afraid, I don’t like using brick acid though. as I have said on the blog many times before, it is just too strong, normally it is based on hydrochloric acid and that is not the best product. It is too aggressive, it will damage the grout in the joints and could also corrode any metals in the vicinity.
It is safer to use a proprietary product based on phosphoric acid or equivalent – the down side is it is not as strong, so takes more effort and more passes – but this would be my recommendation. taking the tiles up and starting again is messy, and you have to prepare the surface again, long winded and expense you don’t need – I would persevere as discussed
Hope that helps
Ian
I have rainbow sandstone for my hearth on my fireplace .. It has some marks on it from dropped wet mortar and then my contractor scraped it off and left a mark. How can I get this/these marks off? Thank you so much!! It’s very upsetting !
Typically you need an acid based cleaner for removal of mortar marks. However, be careful:
First check to see that your particular sandstone is NOT sensitive to acids – some are, esp if they are polished.
If it is safe to use an acid, then try a mild phosphoric acid based cleaner first
Do not go straight for a brick acid based on Hydrochloric (muriatic) unless you absolutely have to.
One other tip: pre-wet the stone to saturate it before applying your CORRECTLY DILUTED acid cleaner – this also helps to minimize any acid etching of the stone itself.
hope this helps
Ian
Hi Ian
I know this thread is a little old now, but hope you can help.
We had a builder re-tile our bathroom. Some of the edges aren’t particularly neat, as there is grout residue making for uneven lines. It’s dark grey grout on white porcelain metro tiles. Please could you advise on the best and/or easiest way for me to remove the untidy grout around the edges?
We had some issues with this builder, so need to rectify this myself now.
I Rob,
Assuming this is wall tiles? – (floor tile grout may be a bit harder but remedy is the same). This is not grout haze or residue you are dealing with but actual grout, over-applied to the edges and not cleaned up properly. So now it is set and presumably quite hard. Wall grout can sometimes be quite powdery. If it is very hard, try using a scraper – if you can find one that is stiff/hard enough that is made of plastic try that as it won’t damage the tiles. If not it is a very careful scraping with a metal edge (blunt chisel, paint scraper or Stanley blade for example) be very careful though as you can slip and hurt yourself and/ or damage the tiles. Also worth trying, if the grout is soft and powdery is a white nylon scouring pad – rub up and down the edges – try this first , rub up and down the edge in the direction of the grout joint, you might be able to clean up the grout lines without damaging the tiles or digging into the grout further than necessary.
Hope this helps
Ian
Hi, I have painted my tiles in my bathroom and then to clean up the grout I have applied a sponge applicated unibond grout reviver. I have left it to dry for too long and there is loads of residual reviver around my tiles. I have attempted to remove it with soapy water and a cloth but all it seems to do it remove the paint from my new tiles, help me please.
Hi,
OK, not sure how to help here. Most people when they paint over tiles, tend to paint the grout at the same time with the same paint. Presumably, the reason for this being that they have decided their tiles are too old or beyond cleaning etc and don’t have the budget or time to retile – so they go over the whole thing with paint to ring the changes. I do not know the precise formulation of the grout revive you have used but it sounds like it is tougher than the paint – so any means of removing it, either chemical or mechanical are likely to take the paint off too.
Soapy water and a cloth does not normally remove paint, so I am guessing this is actually getting in under the TILE PAINT and re emulsifying that. Try a white nylon pad even the type for scouring dishes (white nylon scourer on sponge, often sold for pennies in sets of 3 or 6 in super markets – but make sure it is WHITE, not green or black). Try this with soapy water first, if this does not remove the reviver you pay have to try a paint stripper/solvent (try a little nail varnish remover to test this out before buying paint stripper) this will obviously take the tile paint off too. Also try a plastic scraper (plastic not metal so as not to scratch anything).
I cannot see anyway of removing the residue without taking some of the tile paint it is stuck to off as well. So remove the residue, then when dry, carefully repaint/touch-up the tile paint.
Hope this helps
Ian
Hi Ian,
We have had porcelain slabs laid outside with residue grout left on, not helped with the weather being so hot. Would you have any advice as to the best way to clean it? Thank you very much.
Hi, depending on what type of grout was used, typically a mild acidic cleaner, based on phosphoric acid or similar should be fine. DO NOT USE A BRICK acid – way too strong and will damage the grout. If you have a lot to do then you may benefit from hiring a rotating scrub brush machine. Plenty of rinsing then with clean water, as it is outside you should be able to hose it all away.
Hope this helps
Ian
Hi…the builders I had in mopped the whole of my downstairs with a mop covered in tile grout residue that was from my bathroom upstairs and left it So the brown grout originally there is now white any ideas on how to get it back to brown ?
Hi,
OK, I am assuming you have tried scrubbing it off with a stiff brush and some water? If not I would at least try that first, making sure to flush out and rinse away the water frequently so as to not allow any of the white grout residue to re-settle.
If you have tried that then you have a slight dilemma; if the white grout has got a good hold on the brown then you may have to resort to using a mild acidic cleaner, such as our Grout HaZe Plus. The problem though is that using any acidic cleaner on grout can etch the grout – mild etching is not usually a problem, but it can make the grout a shade lighter (sometimes this is temporary). This is worse though when using dark coloured or pigmented grout – such as brown – the action of cleaning with such a cleaner can remove some of the borwn colour.
You could try a small controlled test:
1) Find an area that is less conspicuous
2) Pre-wet the grout with plain water, just to saturate the grout, not to have the floor covered in water
3) Apply a small test amount of a very dilute Grout Haze Plus (or similar product based on phosphoric acid, not a brick cleaner!) – you could try a dilution of 1 part cleaner to 10 parts water
4) Agitate gently for a couple of minutes then pick up the dirty water. Then rinse with fresh clean water – to flush out any remaining traces of cleaning solution. If using a mop to pick up the dirty solution you may have to rinse several times to ensure you have flushed it adequately – a wet vac would make the job easier if you go ahead and treat the whole floor after a successful test.
5) Leave the test area to dry out completely for 24 hours to check if any it has on removed the white residue, and what effect if any, it has on the brown.
Hope that helps
Ian