How to fix wet spots of new grout?

Question

Hi everyone, so I attempted to re-grout my shower floor yesterday, using the pre-mixed Davco 2L Ready To Use Easy Grout. It's been around 16 hours now and most of the grout looks dry except for the 3 spots near the edge where the shower floor meets the wall that are still a bit damp. Their colour is also brighter and not as grey as the surroundings. I could pick up some of it with my finger by touching those spots gently.

When scrapping off the old grout I found some sort of wet sandy mud under those 3 spots (that shower hadn't been used for 3-4 days prior). I just dried them up using paper towels and went on with applying the new grout. Now I'm getting worried about them not ever drying up and curing properly.

I've attached photos of before and after grouting, with the 3 spots I mentioned about. First time I did it so sorry about the awful grouting job!

Will they dry up eventually if I give more time? If not, what can I do to fix it other than regrouting again?

Thanks for any advice
oldnew grout
wet spot topwet spot left
wet spot right!

EricL · Answer

Hello @Phong_N

Welcome to the Bunnings Workshop community. It's marvellous to have you join us, and thanks for sharing your question about grouting.

I suspect that some of your tile's adhesive has failed and is holding water underneath. Although you've removed most of the water it is still damp underneath and is causing the grout to hold water and prevent it from drying off. If the shower is not used for a few weeks there is the possibility that the water will evaporate, and the grout will eventually cure.

At this point in time, I can only suggest using a heat gun to accelerate the drying process of the grout. But please keep in mind that this will not solve your water leak under the tile. If water persists on coming out of the gap of the tile, I suggest engaging the services of a professional tiler. They'll be able to quote you how much the service will cost to remove your tiles and repair your shower floor.

If you need further assistance, please let us know.

Eric