What flexible grout for outdoor tiles with 12-14mm grout width?

[yh]

What is suitable fkexible grouting for grout width of 12-14mm for a 80m2 outdoor terrace.

[MitchellMc]

Welcome to the Bunnings Workshop community @yh. It's sensational to have you join us, and many thanks for your question about grout.

Based on the joint widths you are describing, you would need to use Dunlop Wide Joint Grout, as it is specifically designed for larger joints. Our flexible grouts are only suitable for joints up to around 8mm maximum, so they would not be appropriate in this case. To help make sure you are using the best product for your situation, could you let us know a bit more about why you feel a flexible grout is required, for example, movement, substrate type, or the area being tiled?

Please let me know if you have any questions.

Mitchell
 

[yh]

Hi Mitchell,

Tks for your reply. My terrace Width 8m x length 10m has already a flex silicon based grout which has been done 18yrs ago, but still look good. There one line each longitudinally and laterally placed at the middle of the whole terrace.  I am already using the Dunlop wide grout to replace old grouting. Just wondered if i needed an extra flex at the edges, one tile away from the sides. The terrace faces west intense afternoon sun.  Am i overthinking the need for the flex grout?

[MitchellMc · Accepted solution]

It sounds like that silicone-based grout is for an expansion gap, and you'd typically use a polyurethane sealant like Sikaflex 11FC for those @yh. If your existing grout has been good for that long, I would suggest mimicking what they have done. Use solid cement-based grout where they used cement-based grout, and Sika where there are silicone joints.

I don't see the need to add any additional flexible joints.

Mitchell

[yh]

Final question, Mitchell.  Is it critically necessary to apply grout sealer for the Dunlop color wide grout?

[EricL]

Hello @yh 

It would definitely help keep the grout clean and water ingress into the grout at a minimum. If you still have enough resources for the sealer, I suggest sealing it.

Eric