Can I Re-tile on old drypack?

[Jrichardson30]

I have a new shower I’m working on and laid some tile on half the floor that after I installed (only been down a few days) we decided we didn’t like and I tore it out. So now what can I do? It’s a 2” drypack w redgard preslope underneath. Obviously the bed is in need of some leveling and filling some divots. Do I need to pull it out down to redgard and redo entire top bed or is there something I can use to patch and smooth so I can lay the new tile that we do like? I know thinset isn’t an option bc there at some spots that will be a little more than 1/4”. Can I take it down an inch or so and put a new layer of drypack on it?

Btw thanks for all the great posts here. Without it I would not have gotten this far. I just haven’t found one by someone as dumb as me needing to redo the tile they just put in and ripped out. All advice is appreciated!

[CaliGrown]

I’d clean off the dust and crumbly/loose junk. Then take some thinset and fill in your holidays and tightly skim coat/burn-in the whole mud bed, let it dry up then tile when you’ve got it flat again. Anything worse than 3/8” I’d slurry coat it and fill it with some deck or mason mix.
Did you flood test your pan before putting down your final mud bed?

[Gregk2]

Can you give more details of how that base was done and of the drain? If you have redguard under the drypack what happens to water that gets under the tile and grout? Seems like it would be trapped there. Are there holes in the side of that drain?

[Jrichardson30]

Caligrown, thanks for the advice! Flood tested for 3 days. No leaks. Drain is linear as you can see but fits into a wonderdrain, so functions just as a tradition shower w water going into weep holes in drain beneath top bed. Preslope-lots of redgard-drain flange-top bed made w dry pack and then tile on top. So pretty traditional, nothing crazy. I may try the thinset but think may be deeper than 3/8. What product would you recommend as a mix? Something that will pull easily would be best since I am not great at this...yet.

[CaliGrown]

Awesome job with flood testing!!

For the deep pockets/fill, take thinset mixed loose like a pancake batter to use as your slurry coat(this will bond your fill material to the existing mud bed). Then take what you used for the dry pack (deck-mud) or you can use some type-s mortar/Mason mix mixed stiff or to the same consistency as dry-pack to get your deep fill done. Next, my preference is to take your loosely mixed thinset and use the flat side of your trowel to skim coat the mud bed to make it nice and tidy/ready for tile. When that’s hardened take a wood float or rub brick to knock down any humps/high spots if you have any. Clean up any dust/debris, give it a wipe down with the sponge, then you should be golden for tiling like a mad man!

[Jrichardson30]

Thanks for the details Christopher! Please bear with me as this is new territory for me so I have few more questions. I am with you on using the first base of loose thinset to basically skim coat and create a tight surface for the next layer to bond to, correct? Put that down and then let it dry? Or while it's wet, put down the s-type mortar or drypack? All in all, I think the deepest pockets are 3/8-1/2" at the deepest. I a non modified thinset and Versabond thinset. Which would you recommend using for the skimming?
Thanks again! I really appreciate your advice more than you know!

[cx]

Welcome, Jeffery.

You can certainly do what you and Christopher are planning, but I'm gonna suggest that what you really want to do is remove your entire top layer of deck mud from that shower receptor and do it over with the correct deck mud material.

The object of any traditional shower receptor construction is to allow for a water in, water out type of top mud bed that allows any moisture that enters the mud bed (there will be a lot) to pass easily through the porous deck mud to the drain's weep holes and also to evaporate easily through the tile surface.

With your patching with thinset mortar and masonry mortar you'll be essentially defeating that system. You'll also be introducing lime into the mix that can speed up the clogging of your drain's weep holes, even if the weep holes have been somewhat protected during construction.

Deck mud is dirt cheap. DIY labor is free. Why not make a new mud bed that you know will work properly?

My opinion; worth price charged.

[CaliGrown]

CX is 100% deck mud is pennies. Water in, Water out system relies on having a porous mud bed. Since you’re dealing with up to 3/8”-1/2” pockets to fill, just take and fill ‘em with your thinset, when it dries and shrinks pass over the area to skim it out flat. Then tile away, tearing out your mud bed you risk puncturing your waterproofing layer.

[Jrichardson30]

Thanks CX...I followed your suggestion, tore it out, patched a few spots where I broke through the redgard and redid it. I mixed sakrete sand mix with extra sand, 5:1 and it packed, screeded out nicely. But when I cleaned it off today, it had lots broken spots and some parts where it was sand all the way down to the preslope. I am super frustrated. Apparently I just don’t have what it takes to get this right. What looked like a good solid substrate for tiling is not a crumbly mess. Maybe I shouldn’t have mixed the extra sand? It was dry but held a shape when when I squeezed it in hand and didn’t leave my hand wet. It’s just as I discovered...this part is an art and I ain’t no Picasso. I originally hired some guys to do the pan for me who are professional tile setters but they left me with a crooked drain, a slope to one of the corners ANd they didn’t do a preslope (which I figured out when I tore their shotty work out. So I figured I would try my hand at it. And now here I am. Wishing I had just purchased the prefab shower pan and been done with this thing months ago. Oh well, lessons-many many many-lessons learned and skill limits discovered. I will get it sorted out but I am so ready to be done with this part of the job.

[Jrichardson30]

And Christopher, thanks for the help with the thinset method. That’s the route I am taking with repairing this time because I can’t do the whole thing over again. I just don’t have it in me????

[cx]

Originally Posted by Jeffery

...it had lots broken spots and some parts where it was sand all the way down to the preslope.

That sort of problem is usually the result of insufficient mixing of the dry materials before adding water, Jeffery.

Ain't no rocket surgery involved with mixing or placing deck mud, but it does require some attention to detail. One of the best aspects is that the materials for the mix are dirt cheap and a fella can afford to practice as much as he needs to learn to get it right.

My opinion; worth price charged.

[Jrichardson30]

Maybe So. I did small batches, mixed in buckets and used an auger for mixing. I mixed before adding water but apparently something didn’t mix right. Next time I will buy sand and cement and mix instead of the sakrete sand mix. I appreciate all the advice CX and Chris!

[Jrichardson30]

Okay, so I redid it AGAIN! And this time I think I got it right. Seems to be solid, smooth and no pockets/holes of loose sand. So now I am ready to get my tile down. The sakrete sand mix (added sand for 5:1) says you must tile 16-24 hrs after putting the mud down and after 24 hrs, it enters a green state and must wait 28 days. Is that accurate? If so I gotta get my tile down this afternoon or wait a month. Please advise. Putting down a 3/8 marble mosaic...if that matters. After 4 times, I think I finally have the whole dry pack thing figured out. Thanks again for all the advice and posts here!