Looking for grey epoxy concrete crack filler

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peng1nz

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#323094 25-Oct-2025 12:33

I want to repair (hide) a non-structural crack in my garage entrance. The crack is in the outdoor strip in front of the garage door. I have ground it out about 5mm wide, 10mm deep. I'd like to find a coloured epoxy filler I can fill and then sand back to smooth but not have to paint. Hoping I can find a light grey to match the original concrete. Crack is 25cm long so I only need a tiny qty. (<20ml)

Any suggestions for a coloured product suitable for outdoors?

endor

2 posts

Wannabe Geek
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#3427909 25-Oct-2025 12:47

https://www.ardex.co.nz/product/ardex-ra-56/#

qwertee

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#3427914 25-Oct-2025 13:42

Look for a Sika product

Here is a link from a quick google search.

We had a long crack in our garage , but it was repaired professionally

They cut a V line in the groove of the crack, sealed it, ground the whole floor and used a Sika epoxy 2 part mix to coat the entire garage.
Maybe not what you are aiming for.

https://nzl.sika.com/en/diy-trade/concrete-repair-protection/repair-cracks-inconcrete.html

Jase2985

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#3427933 25-Oct-2025 18:04

I've used Regis products before and they were good. Specifically, their fairing cream and some of the concrete epoxies.

https://www.regiscoatings.co.nz/Products/Instance/Floor-Repair/

bebek

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#3427949 25-Oct-2025 19:59

Batman

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#3427988 26-Oct-2025 05:20

bebek:

You may like to check on these:

https://www.bunnings.co.nz/gripset-betta-500ml-waterproofing-repair-compound-concrete-crack-filler-500ml_p0269375

https://www.bunnings.co.nz/nordsjo-professional-330g-rapid-repair-filler-tube_p0333055

https://www.bunnings.co.nz/crc-750g-121-concrete-filler_p0203540

hi can i ask what concrete mix can i get that is as waterproof as possible? i need around 1L to fill a big gap and it is between outdoor and indoor so i need it to be as waterproof as possible

thanks

bebek

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#3428016 26-Oct-2025 10:35

Concrete itself is not waterproof as liquid will be absorbed in. However, water or dampness will make concrete stronger over time.

If you want to prevent water seep into concrete then you'll need a coating e.g. concrete paint, concrete sealer etc.

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Batman

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#3428046 26-Oct-2025 14:32

bebek:

Concrete itself is not waterproof as liquid will be absorbed in. However, water or dampness will make concrete stronger over time.

If you want to prevent water seep into concrete then you'll need a coating e.g. concrete paint, concrete sealer etc.

absorbing liquid is ok, better than the gaping hole currently. i read there is high waterproof concrete and low waterproof concrete, something like that, where do i get the high waterproof type to fill the hole/gap?

bebek

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#3428241 27-Oct-2025 15:38

TBH i don't know. Have a look at cemix website. Their products is anything related to concrete.