How to replace outdoor tile grout?

[MichaelE]

I need to do some re-grouting on the outdoor tiles around my pool area. The grout has some cracks and is starting to let in the weeds. I also have a couple of spots where the grout has fallen out.

Are there products that I can go over the existing grout rather than grinding away and starting again?

 

[BradN]

Hi @MichaelE, and welcome to the Bunnings Workshop community. It's great to have you here.

One of our resident D.I.Y. experts, @EricL, will be back on the site tomorrow. In the meantime you might want to take a look at this discussion, How can I re-grout my outdoor brick paving, in which Eric was able to provide advice to another member.

 Brad

[MichaelE]

Thanks for the response and the link. Was really hopeful that I could use one of the premixed grouts to just go over the top of the damaged areas, but looks like its a bit more involved than that.

[MitchellMc]

Hi @MichaelE,

Going over the degraded and damaged grout would be considered a band-aid repair. It could be successful and might give you several years before needing to be done again. Typically you'd want to remove the degraded areas and resolve the issues which have caused the cracking to occur. The cracking and separation are due to movement, and that is why the joints in pavers are so often filled with sand instead of grout.

For the areas of missing grout, it would be best to chip out any adjacent grout that is loose and remove it. You can then patch the area with a mortar tinted to the correct colour with oxide. For the areas where the grout has separated from a paver on one side yet is still in good condition, you'd be best filling the crack with a flexible filler like Mortafil. Mortafil is highly flexible and will cope better with movement than a cement-based product.

Please let me know if you have any questions.

Mitchell

[MichaelE]

Thanks very much Mitchell. Are there any pre-mixed mortar products similar to the Mortafil?

Not super confident to mix mortar and then tint the correct colour.

Cheers,

Michael

[EricL]

Hello @MichaelE

The only products that are pre-coloured are the Dunlop and Davco grout systems. The only limitation they have is that they are only rated to cover a gap of up to 8mm. Anything past that and the product will not work properly. For larger gaps, the other choice is to use Davco Slate and Quarry grout which can cover a gap of up to 12mm. If you have larger gaps to fill, I recommend using mortar to fill the gaps.

If you are curious as to the finish of the mortar, I propose purchasing a small bag and mixing a small batch to give you an idea of the finish it will have. You can use that small batch to patch any holes along your driveway or if you have some chipped brickwork that needs patching. Please keep in mind that as time passes the colour of the mortar will fade and become almost like a neutral grey. 

If you need further assistance, please let us know.

Eric