Hello all, Just dropped in, need advice on adhesives and grout types - Tile Advice

[Zoot]

(Excuse my mistakes, English isn't my first language)

Moved to Scotland recently, I work in the oil industry. Not a great place to be these days, but am enjoying the cheaper petrol.

I just ripped up all the shower floor tiles in my new house (a small remodelled stone barn) because the grout was cracked and the tile adhesive had decomposed somehow to a powdery paste and were all very loose. They were laid on the surface of a screed covering that overlays the floor heating circuits. I suspect that expansion and contraction over the last 3 years cracked the grout and that water leaked under the tiles but I'm not sure. The shower is in a utility room in a configuration which I think is called 'wet room'. The water falls on the floor tiles or drops from the tile walls to a drain, in theory.

So I wanted to do it all over and took out all the floor tiles, an easy job because 99% of the tiles were loose due to the failed adhesive. I removed all the degenerated adhesive from the floor and the tiles, and am ready to relay the tiles but I'm stuck here. SO.....

If I repeat what the original builder did I'll probably be doing it all over again in 3 years. Is there a special adhesive for ceramic porcelain tiles that adheres to a screed base and is flexible enough to withstand temperature changes from say 10 degrees Celsius to 40 (ish). And is there a special grout that I need to use this situation?

Any advice heartily appreciated...

 

[Tilerdurden]

Won't go far wrong with bal flexible adhesives and bal grouts. Depending on grout choice if it has limited flexi properties use an admix like gt1. What is the subfloor under the screed and heat mats? If it's timber and no uncoupler has been used this will cause issues in itself. Sounds like there's been movement in subfloor to cause the grout to crack which will have allowed water to penetrate and break your adhesive down.

 

[Zoot]

Won't go far wrong with bal flexible adhesives and bal grouts. Depending on grout choice if it has limited flexi properties use an admix like gt1. What is the subfloor under the screed and heat mats? If it's timber and no uncoupler has been used this will cause issues in itself. Sounds like there's been movement in subfloor to cause the grout to crack which will have allowed water to penetrate and break your adhesive down.

 

[Zoot]

Thank you very much for your reply Tilerdurden. I'll check the bal adhesives and grouts out. I didn't know that you could add other stuff in to grout like you suggested, it's a good heads up.

The screed is about a foot deep. From looking at pictures of the installation in 2012 before I moved in it was placed on a polystyrene base into which the heating hose circuits were fixed. This base is about an inch and a half thick. It lies on a concrete slab of about 6 inch thickness, and I don't know what's below that. There may well have been some movement in the subfloor, I don't know and the place was unoccupied until I moved in. There may also have been water other than from the shower itself leaking in to the utility room area. The plaster at floor level has some water damage. It's kind of hard to say exactly what happened.

Thanks again for the suggestions.

 

[Tilerdurden]

Thank you very much for your reply Tilerdurden. I'll check the bal adhesives and grouts out. I didn't know that you could add other stuff in to grout like you suggested, it's a good heads up.

The screed is about a foot deep. From looking at pictures of the installation in 2012 before I moved in it was placed on a polystyrene base into which the heating hose circuits were fixed. This base is about an inch and a half thick. It lies on a concrete slab of about 6 inch thickness, and I don't know what's below that. There may well have been some movement in the subfloor, I don't know and the place was unoccupied until I moved in. There may also have been water other than from the shower itself leaking in to the utility room area. The plaster at floor level has some water damage. It's kind of hard to say exactly what happened.

Thanks again for the suggestions.

Sounds like the proverbial can of worms has been well and truly burst wide open.

Are you saying the concrete slab is sitting on a bed of polystyrene?

 

[Zoot]

Sounds like the proverbial can of worms has been well and truly burst wide open.

Are you saying the concrete slab is sitting on a bed of polystyrene?

 

[Zoot]

Sorry if I mislead you, my expression maybe was not that great.

The concrete slab is the base layer, the polyfoam sheet above it holds the heating circuits in place and the screed is laid on top of that.

 

[Tilerdurden]

Sorry if I mislead you, my expression maybe was not that great.

The concrete slab is the base layer, the polyfoam sheet above it holds the heating circuits in place and the screed is laid on top of that.

Have you got images you can upload zoot?

 

[Zoot]

Have you got images you can upload zoot?

I don't have anything that shows more than the surface of the screed today after I took the tiles up. I'll try to see if I can dig out anything from the time the floor was put in but I'm not hopeful....

 

[ATZ Tiling]

I am up in Aberdeenshire and know these anhydrated screed floors well. Floor needs to be slightly sanded first, then primed(usually a few times), recommend using a decoupling membrane which is stick down with flexible tile adhesive, then last of all Tile as usual on top.

 

[Zoot]

That sounds like an interesting idea. I'll look into that. Thanks very much for the suggestion.