How long does it take for the concrete under tiles in bathroom to set?

[jack71]

We have a tiler here putting new tiles on the walls and floor of our bathroom. 

 

Yesterday he finished the white tiles on the walls. Today he is about to finish the black floor tiles. I asked him how long does it take for that concrete under the tiles to dry. He said 3 hours. He said he will come back later today to put the grout in between the gaps on all surfaces. 

 

Is that correct. Can he stand on that floor after just 3 hours?

 

thanks

[Bangkokhatter]

I would wait at least 24 hours, it may look dry around the tile edges but underneath will certainly not be dry after 3 hours.

He will probably tell you it's special Thai quick drying adhesive ???? 

[DaLa]

When you say 'concrete under the tiles' do you really mean the adhesive (cement based) that he has used to 'stick' the tiles down. If so then it depends on the  adhesive he has used . Rapid set can be as little as 3 hours so all is ok. Problem in this country is reading whats on the bag of adhesive and don't even think about asking anyone in Thaiwatsadoo.  The concrete sub floor (what the house is built on) needs 28 days for each inch of depth , however I've laid tiles on 'drying' concrete before, just takes a little longer for everything to dry out.

[Tofer]

If he's laying the tiles directly on a cement screed as the bonding for the tiles, it will likely take more than 3 hours, even though the screed mix is usually quite dry.

 

I would consider this method carefully, as there is more likelihood of the tiles de-bonding, than with a dedicated tile adhesive. 

[OneMoreFarang]

1 hour ago, jack71 said:

bathroom

Did he make sure everything is sealed against water leakage?

[jvs]

Should be no issue,what you can do is lay a piece of plywood on the tiles that

you are walking/kneeling on.

 

[itsari]

24 hours for floor adhesive to dry before any weight placed on top of the tile .

Many Thais lay floor tiles on cement . One reason why floor tiles lift up in Thailand . 

You do not specify what method was used . Cement needs time to dry as well . 3 hours is not recommended 

[transam]

https://www.uk.weber/tile-fixing/tiling-green-screeds-or-concrete#:~:text=Screeds should be firm enough,be clean and surface dry.

[Bday Prang]

1 hour ago, DaLa said:

When you say 'concrete under the tiles' do you really mean the adhesive (cement based) that he has used to 'stick' the tiles down. If so then it depends on the  adhesive he has used . Rapid set can be as little as 3 hours so all is ok. Problem in this country is reading whats on the bag of adhesive and don't even think about asking anyone in Thaiwatsadoo.  The concrete sub floor (what the house is built on) needs 28 days for each inch of depth , however I've laid tiles on 'drying' concrete before, just takes a little longer for everything to dry out.

                  The concrete does not require 28 days for each inch of depth that is just not true, if that was the case a normal 4inch or 6 inch slab would be unusable for 4 to 6 months. !! and multi storey buildings would take many many years to complete

                  The 28 days often mentioned regarding concrete strength, is the time the concrete takes to reach its nominal "design" strength ,( regardless of its thickness) , which is not something to worry about when considering a ground bearing slab for a normal house,  Rather is a figure used for design calculations for load bearing members  on multi-storey buildings for example, even in that situation the supporting formwork for each floor can normally  be removed  after 7 to 10 days as the concrete will be fully self supporting by this time even though it will not have achieved its full design strength!. 

                 A normal ground bearing floor slab can easily be walked on after 8 to 12 hours, even sooner in these hot temperatures  in fact as soon as it is hard to the touch, and, it is perfectly normal practice to build block walls upon the slab the day after pouring.

     Purpose made tile adhesive cement (poon gao) is actually a little slower setting than a normal sand and cement mix and personally I would leave the grouting up till the next day  .Although what ever was used,  in this hot weather I doubt there will be a problem after 3 hours.

[sometimewoodworker]

3 hours ago, DaLa said:

When you say 'concrete under the tiles' do you really mean the adhesive (cement based) that he has used to 'stick' the tiles down. If so then it depends on the  adhesive he has used . Rapid set can be as little as 3 hours so all is ok. Problem in this country is reading whats on the bag of adhesive and don't even think about asking anyone in Thaiwatsadoo.  The concrete sub floor (what the house is built on) needs 28 days for each inch of depth , however I've laid tiles on 'drying' concrete before, just takes a little longer for everything to dry out.

You are getting confused between concrete and wood. Concrete cures at a uniform rate however thick it is, wood dries from the outside so seasoning is given as a time per inch of thickness.

[jack71]

10 hours ago, Tofer said:

If he's laying the tiles directly on a cement screed as the bonding for the tiles, it will likely take more than 3 hours, even though the screed mix is usually quite dry.

 

I would consider this method carefully, as there is more likelihood of the tiles de-bonding, than with a dedicated tile adhesive. 

how long will it take for the grout to dry. they come tomorrow to put the grout in between all the gaps of the tiles. How long should we wait before using the shower in there?

thanks

[OneMoreFarang]

7 hours ago, jack71 said:

how long will it take for the grout to dry. they come tomorrow to put the grout in between all the gaps of the tiles. How long should we wait before using the shower in there?

thanks

You should ask them and follow their advice.

Because if you would use it too early then they won't repair it on warranty.

[2baht]

I would not take the word of the "tradesman", to be sure, you need to watch the adhesive/grout dry yourself, should be dry in 4 to 6 hours. Get comfortable. 

 

 

Edited June 25, 2022 by 2baht

[Bill97]

12 minutes ago, OneMoreFarang said:

You should ask them and follow their advice.

Because if you would use it too early then they won't repair it on warranty.

Do you know how to waterproof seal a tile floor?  If so please enlighten us.

[Lacessit]

Concrete does not "dry". It's actually better to keep it moist as it cures. The curing reaction is the lime in the concrete reacting with atmospheric carbon dioxide to form calcium carbonate.

Concrete usually has load-bearing capacity after 24 hours, for optimum strength about 3 days.

[LarrySR]

You should set up a YouTube camera when the tradesman comes into work tomorrow and you explain you've been on the internet 'doing research' and he's doing things all wrong.

 

 

 

 

[OneMoreFarang]

2 hours ago, Bill97 said:

Do you know how to waterproof seal a tile floor?  If so please enlighten us.

 

 

[OneMoreFarang]

2 hours ago, LarrySR said:

You should set up a YouTube camera when the tradesman comes into work tomorrow and you explain you've been on the internet 'doing research' and he's doing things all wrong.

And better call an ambulance on standby. ???? 

[Excel]

Considering the time this thread has been running it should be set by now 

[sandyf]

22 hours ago, DaLa said:

When you say 'concrete under the tiles' do you really mean the adhesive (cement based) that he has used to 'stick' the tiles down. If so then it depends on the  adhesive he has used . Rapid set can be as little as 3 hours so all is ok. Problem in this country is reading whats on the bag of adhesive and don't even think about asking anyone in Thaiwatsadoo.  The concrete sub floor (what the house is built on) needs 28 days for each inch of depth , however I've laid tiles on 'drying' concrete before, just takes a little longer for everything to dry out.

The OP said the tiler was laying "new" tiles.

[Bill97]

2 hours ago, Bill97 said:

Do you know how to waterproof seal a tile floor?  If so please enlighten us.

 

34 minutes ago, OneMoreFarang said:

 

 

So you don’t have a clue how to do it in Thailand.  Post post post but nothing.

[OneMoreFarang]

1 hour ago, Bill97 said:

 

So you don’t have a clue how to do it in Thailand.  Post post post but nothing.

It's always great if people ask for advise and then they don't want to listen.

Maybe you or your "technician" doesn't do it this way. But that doesn't mean professionals also have no clue.

Feel free to do it the Thai way ...

[transam]

4 hours ago, 2baht said:

I would not take the word of the "tradesman", to be sure, you need to watch the adhesive/grout dry yourself, should be dry in 4 to 6 hours. Get comfortable. 

 

 

But not dry enough for water use....

[Bill97]

1 hour ago, OneMoreFarang said:

It's always great if people ask for advise and then they don't want to listen.

Totally worthless advice, no reason to listen.

[OneMoreFarang]

13 minutes ago, Bill97 said:

Totally worthless advice, no reason to listen.

The guy who made the video does this since 30 years or so. How about you?

If you are such a big expert then why don't you share your expertise? Or is there nothing to share?

[Tofer]

14 hours ago, jack71 said:

how long will it take for the grout to dry. they come tomorrow to put the grout in between all the gaps of the tiles. How long should we wait before using the shower in there?

thanks

Did they lay the tiles on the cement screed or on a tile adhesive layer?

[Bill97]

1 hour ago, OneMoreFarang said:

The guy who made the video does this since 30 years or so

Where?  This is Thailand,  has he been using that method here?  I doubt it. No sense in talking about methods that nobody here knows and for which materials are not available.

[jack71]

On 6/24/2022 at 2:10 PM, Bday Prang said:

                  The concrete does not require 28 days for each inch of depth that is just not true, if that was the case a normal 4inch or 6 inch slab would be unusable for 4 to 6 months. !! and multi storey buildings would take many many years to complete

                  The 28 days often mentioned regarding concrete strength, is the time the concrete takes to reach its nominal "design" strength ,( regardless of its thickness) , which is not something to worry about when considering a ground bearing slab for a normal house,  Rather is a figure used for design calculations for load bearing members  on multi-storey buildings for example, even in that situation the supporting formwork for each floor can normally  be removed  after 7 to 10 days as the concrete will be fully self supporting by this time even though it will not have achieved its full design strength!. 

                 A normal ground bearing floor slab can easily be walked on after 8 to 12 hours, even sooner in these hot temperatures  in fact as soon as it is hard to the touch, and, it is perfectly normal practice to build block walls upon the slab the day after pouring.

     Purpose made tile adhesive cement (poon gao) is actually a little slower setting than a normal sand and cement mix and personally I would leave the grouting up till the next day  .Although what ever was used,  in this hot weather I doubt there will be a problem after 3 hours.

how long will it take for the grout to dry. they come tomorrow to put the grout in between all the gaps of the tiles. How long should we wait before using the shower in there?

thanks