minerit or plaster? Help!

[Plupp 23608]

You are welcome to explain to me what is wrong with it.

Claiming that the waterproofing layer would not be a good surface to install tiles on is absurd. What do you base that statement on?

The tiles are not waterproof. The grout is not waterproof. The adhesive is not waterproof. To go and perforate the only waterproof layer in the construction to install a (non-waterproof) board that serves no practical function would be madness.

...Imagine then this water between and behind the tiles because the joints are not sealed with grout.

Again; the grout seals nothing. It absorbs moisture like a sponge - if you shower on a tiled wall, you have filled the construction with water in a couple of minutes.

Bathrooms are called hygiene rooms because we humans wash ourselves there, but a bathroom that is not hygienic is not a pleasant place to maintain your hygiene.

I assume you are referring to tiles that are "rectified" (ground to exact dimensions) when you talk about "jointless" setting? In practice, these are set with minimal joints (1-2 mm) and grouted because conditions are never so perfect that it's possible to set the tiles flush without gaps. If we disregard that and assume they are indeed set tightly against each other and not grouted, it won't mean that more "dirty water" will get behind the tiles than with a traditional setting. These tiles are almost always made of porcelain stoneware (E-value <0.5%) which ensures less water behind the tiles than you would get with a grouted ceramic tile.

 

[imported_Byggaren]

ACME:

To claim that the moisture barrier would not be a good surface to tile on is absurd.
What is that statement based on?

A fuktspärr has only one function to serve: to act as a moisture barrier. It has no load-bearing function.

The tile is not waterproof. The grout is not waterproof. The adhesive is not waterproof.

Thank you for the information! I knew that long before I turned 40, and now I am >70. I have also been involved (as Riksbyggen's representative in the VASKA project) in developing today's regulations for how to waterproof bathrooms.

To stand and perforate the only waterproof layer in the construction to install a (non-waterproof) board that serves no practical function would be madness.

It is always risky to make holes in a moisture barrier, but if done carefully and professionally, the risk is very small.

There is, however, a much greater risk of putting a load-bearing function on the moisture barrier that it is not designed to handle. Both vertically against the wall and perpendicularly outward from it.

Therefore, tiles should not be placed directly on the moisture barrier but on a substrate that can handle the load. The substrate may eventually fail, but the moisture barrier underneath remains intact, as has been proven by numerous water damages and the statistics from insurance companies in cases where it hasn't happened.

Again; the grout seals nothing. It absorbs moisture like a sponge - if you shower on a tiled wall, you have filled the construction with water within minutes.

No. Nothing more than the tiles themselves is moisture-proof. LTH demonstrated this in a practical test many years ago when they mounted tiles on a glass sheet and let a handheld shower run water against the surface. It was possible to see from the back how water from the grout spread under the edge of the tiles, but no water came through the tiles.

I assume you mean tiles that are "rectified" (ground to exact dimensions) when you talk about "groutless" installation?

Yes.

In practice, these are installed with minimal joints (1-2 mm) and are grouted because the conditions are never so good that the tiles can be laid flush without grout.

Which proves that the very idea of these tiles is absurd.

If we disregard that and assume that they are indeed laid directly against each other and not grouted, it will not result in more "dirty water" behind the tiles than with a traditional installation.

Well! There is a difference between capillary absorption and free access for water. In the first case, the dirt remains on the surface of the grout; in the second, the dirt is right against the wall.

These tiles are almost always made of porcelain stoneware (E-value <0.5%) which guarantees less water behind the tiles than with a grouted tile.

As I wrote above, it is not through the glazed tile that the water enters, but through the grout. Therefore, the hardness of the tile itself has little significance for capillarity because the glaze is dense (fired in a kiln).
_________________________
Byggaren

 

[jon_h]

A moisture barrier has a single function to fulfill: to act as a waterproof layer. It has no load-bearing function.

That's exactly what it has. It has three functions: to adhere to the substrate, to be waterproof, and to create a surface that the adhesive can stick to. It excels at all three. Adhesion in both cases is well above the required 0.5 MPa.

It is always risky to make holes in a moisture barrier, but if done carefully and professionally, it's a very small risk.

Absolutely. But doing it completely unnecessarily is still incredibly foolish. Moreover, your construction is a prime example of non-professional execution, as you have invented it yourself and do not anchor it in either industry standards or any supplier's construction solution.

However, there is a significantly greater risk of imposing a load-bearing function on the moisture barrier that it is not intended to bear. Both vertically on the wall surface and perpendicular out from it.

As stated, it is intended for that and handles the load with an exceedingly high margin.

Byggaren, when you make claims that no one else in the industry (whether it's Byggkeramikrådet, GVK, insurance companies, or material suppliers) agrees with, you bear a fairly large burden of proof. Can you provide a single source that your construction has been tested? The constructions that material suppliers provide, or that are described in BBV, are carefully tested in the lab and in hundreds of thousands of wet rooms in practice. I don't think a single wet room is built as you describe, possibly except for your own.

 

[Plupp 23608]

A moisture barrier has a single function: to serve as a sealing layer. It has no load-bearing function.

As jon has already pointed out; Yes.
It is, as you should know, developed and tested to withstand that load.
In the fifteen years I've worked with insurance claims, I've never seen (or heard of) a damage caused by the sealing layer coming off.

Thanks for the information! I knew this long before I turned 40, and now I'm >70.

Wow. Impressive. Really.

I've also been involved (as a Riksbyggen representative in the VASKA project) in developing today's regulations for making wet rooms watertight.

That just makes your statement even more peculiar.

Nothing more than the tiles themselves are resistant to moisture.

Glazed tiles are waterproof, but a tile with a high E-value and glaze only on the front will allow moisture to penetrate more easily than, for example, a granite ceramic or glass tile that only allows moisture to migrate through the joints and adhesive.
Hence my reasoning around granite ceramic tiles placed directly next to each other.

However, that entire discussion is irrelevant because the tiles are almost always grouted, and that wasn't the main point of my first post.
The point was that it's absurd to put minerit on the wall as a solution to a non-existent problem.
Consider that this is a public forum for DIY enthusiasts, and people might actually believe what you're writing is true.

 

[Linus_E]

but the way I thought of doing it can't be wrong, can it?
should be right to get a smooth surface?

 

[jon_h]

It should work, provided the foundation is stable. So no loose tiles or old plaster that is detached.

Builder, it feels somewhat symptomatic that you make strange claims in different threads, and when the discussion becomes difficult for you, you simply stop responding in the thread. I would appreciate it if you either addressed the arguments presented in the thread or had the humility to say that you might have been wrong.

 

[jawen]

A bit ridiculous boring mudslinging in the thread, I think.

What every person knows is that a glazed tile does not let water through (glass is tight)... are we agreed there?

What every experienced bathroom renovator also knows is that if you grout "normally" with a 3 mm grout and water it 3-4 times over a couple of days, it becomes practically almost waterproof inwardly but continues to "breathe" outwardly... are we agreed there?

The grout's purpose is to handle small movements in the wall and to vent moisture from the wall... do we agree?

During a "normal" shower, the grout only becomes wet a couple of mm in, as almost all the water just runs off the tiles/grout straight into the drain... agreed?

Then of course ventilation is a very important aspect in bathrooms... agreed?

So with normal ventilation, normal glazed tiles e.g. 15x15 with 3 mm grout done correctly, you won't have "the construction water-filled in a few minutes of showering" as someone wrote. The problem then lies in one of the performed steps or the bathroom has no or inadequate ventilation, but then the moisture content behind the tiles has slowly, slowly risen to unhealthy levels.

Furthermore, the moisture barrier, the so-called (gummen), should be rolled in 2 very thick layers after rolling adhesion/wall primer, which after drying should be measurable to at least 1 mm thickness, preferably closer to 2 mm.

It should also not be rolled smooth but rolled so a bumpy surface appears, i.e. a very thick layer. These "barbs/bumps" that the moisture barrier creates after drying then increase the adhesion for the adhesive by almost 100%.

And of course, a dust-free surface to start moisture-proofing on is a given.

So I think Imported_byggaren is right about most things except the minerit board, including what he writes about grout-free tiles, because a grout breathes and releases moisture, so that function disappears with grout-free tiles. So that type of tile probably helps in some cases to create long-term diffusion problems.

I only have my approx. 2200 manufactured renovated/newly built bathrooms & 6 years as a Water Damage Technician at JM.AB to support my opinions/experiences.

Best regards, Jawen

 

[jon_h]

What every experienced bathroom renovator also knows is that if you grout "normally" with a 3 mm grout and re-moisten it 3-4 times over a couple of days, it becomes almost watertight facing inwards but continues to "breathe" outwards....do we agree on that?.

No. It is not watertight inwards.

So with normal ventilation, normal glazed e.g. 15x15 tiles with a 3 mm grout applied correctly, you don't get the "construction flooded with water in a few minutes of rinsing" as someone wrote, then the problem lies in one of the performed steps or the bathroom has no or inadequate ventilation, but then the moisture level behind the tiles has slowly, slowly risen to unhealthy levels.

After two minutes, the grout is saturated, and with a number of showers, such a construction is water-filled. If you then stop showering, it takes several months before it dries out behind the tiles. This has been shown through tests at SP. I can certainly dig up the report if you want it. But how unhealthy? The construction can handle 100% humidity, so what's unhealthy about that?

Then, the moisture barrier, the so-called (gummen), should be rolled in 2 very thick layers after rolling with adhesion/wall primer, which after drying should be measurable to at least 1 mm thickness, preferably closer to 2 mm.

I don't understand how you can say "this is how you do it." It entirely depends on which waterproofing system is used. Most today are membranes that are glued up, and the liquid-based systems available require more than two rollings.

So I think Imported_byggaren is right about most things except the minert board, including what he writes about groutless tiles, because since a grout breathes and releases moisture, that function disappears with groutless tiles, so that type of tile probably helps in some cases to create long-term diffusion problems.

Having 100% RH behind the tiles is not a problem. You have that all the time behind the tiles in the shower. That's why the vapor resistance of waterproofing layers is tested by driving between 100% and 50% RH nowadays.

 

[gaia]

Stupid question as a result of the discussion above.
If there are no waterproof grouts, WHY don't they exist then? Why is the underlying membrane/lining the only solution to the problem?
It feels somewhat unsettling to know that you have constant 100% moisture in the wall behind the tiles and that water runs under the floor tiles hopefully finding its way to the floor drain. Ideally, one would want to live without non-tight moldy grouts. If you don't want a well-functioning welded plastic mat in wood constructions... can you not tile in a safer way without the so fragile membrane?
For example, with glass tiles or granite ceramics that barely absorb water, grouted with a waterproof and moderately elastic grout - providing a waterproof bathroom wall in a single work step.
Why aren't there waterproof grouts on the market? Impossible? Inconvenient? Too cheap a solution? Too small a market?
Can someone try to explain it to me?
gaia

 

[jon_h]

The construction behind is designed to handle 100% humidity behind the tiles with a good margin, so watertight joints are not needed. It is not a problem for water to be there. If the grout molds and becomes unsightly, it is due to poor quality of the material, workmanship, or careless cleaning. Or a combination of these factors.

However, there are indeed watertight epoxy grouts. These are however very hazardous to work with, and not something to be done unnecessarily. Additionally, it is difficult to guarantee the seal over time in corners and other joints, where movement joints are often required instead. An epoxy grout would let water in through these small leaks but would more or less completely prevent diffusion out of the construction, and the result would be the same.

Additionally, there are other difficulties, such as how to seal against the floor drain if the ceramic serves as the watertight layer.

 

[Plupp 23608]

What every person knows is that a glazed tile does not let water through (glass is dense).... Are we agreed on that?

Yes, on the surface it is waterproof (but not vapor-proof). However, the glaze is only on the front side, and it's not uncommon for the clay to be visible at the edges of the joints in poorly installed bathrooms. Therefore, a mm of moisture penetration into the joint is enough for the tile's clay to start absorbing moisture.

What every experienced bathroom renovator knows is that if you grout "normally" with a 3 mm joint and water it 3-4 times over a couple of days, it becomes almost watertight inwardly but continues to "breathe" outwardly....are we agreed on that?

No.

The joint's purpose is to take small movements in the wall and to ventilate the moisture out of the wall... are we agreed?

No.
Joints are required to compensate for the tolerances that exist in all construction.
It is partly cosmetic and partly intended to create a cleanable surface. With 15x15 tiles, the joint only constitutes about 5% of the wall's surface, making the drying very slow. As Jon mentioned, it takes a number of (approximately 6-9) months before the wall is dry again.

The joint, during "normal" showering, only gets wet a couple of mm into the joint since almost all the water just runs off the tiles/joints straight down the drain... agreed?

No.

Then, of course, ventilation is a very important aspect in bathrooms... agreed?

Yes.

So with normal ventilation, normal glazed 15x15 tiles with 3 mm joint executed in the right way, you won't get the "construction waterlogged in a few minutes of spraying" as someone wrote

Yes.

then the problem lies in one of the executed stages or that the bathroom has no or insufficient ventilation, but then the moisture content behind the tiles has gradually, gradually increased to unhealthy levels.

Water is not unhealthy - Mold is, but there is nothing on the wet side of the moisture barrier that can mold.

Then the moisture barrier, the so-called (rubber), should be rolled on in 2 very thick layers after rolling with adhesion/wall primer that after drying should be measurable to at least 1 mm thickness, preferably closer to 2 mm.

As Jon already pointed out, you can't generalize like you do - it varies between manufacturers. What they all have in common, however, is that they do not specify how thick the moisture barrier should be applied but in how much per square meter.

So I think Imported_builder is right in most things except the Minerit board, among other things he writes about grouting-free tiles, since a joint breathes and releases moisture, that function disappears with grout-free tiles, so that type of tile probably helps in some cases to create long-term diffusion problems.

As said, the wall will never become dry as long as the bathroom is used.

I only have my approximately 2200 manufactured renovated/newly-built bathrooms & 6 years as Water Damage Technician at JM.AB to back up my opinions/experiences.

2200 bathrooms? What was your role in these bathroom constructions?

 

[gaia]

The construction behind is designed to handle 100% humidity behind the tiles with a good margin, therefore waterproof joints aren’t necessary. It’s not a problem for water to be there. If the grout molds and becomes ugly, it’s due to poor quality of materials, work, or careless cleaning. Or a combination of these factors.

Well, it wasn’t that simple to use tight joints

Mold grows on organic material and that material comes from soap and dirt you wash off which then sticks in the damp grout. I would wish for a grout material of such quality that it withstands that without molding too quickly. It would be good to choose the best when it’s going to be more or less humid all the time between membrane and tiles. I will clean... but would prefer to have the best conditions from the start. Which grout brand is best to handle that?
gaia

 

[jon_h]

There are more or less dense and water-repellent grouts available from most suppliers, some with what is called the "pearl effect." I think it's always worth a few extra hundreds to get a high-quality grout instead of using a standard grout, those usually called "tile grout" or "clinker grout." My personal favorite is Mapei, their Keracolor FF for tiles and Ultracolor Plus for clinkers, but there are many good grouts on the market.

All grouts become unattractive long before the ceramics do, as ceramics have an almost unlimited lifespan. It's entirely possible to re-grout a bathroom when the grout becomes unsightly, but since it's a tremendous amount of work, you naturally want the original grout to stay looking nice for as long as possible.

 

[gaia]

There are more or less dense and water-repellent joint compounds from most suppliers, some with the so-called "pearl effect." I think it's always worth a few extra dollars to get a high-quality joint instead of using a standard joint, the ones usually called "tile grout" or "clinker grout." My personal favorite is Mapei, their Keracolor FF for tiles and Ultracolor Plus for clinkers, but there are many good grouts on the market.

All joint compounds become unsightly long before the ceramics do, as they have an almost unlimited lifespan. It is entirely possible to regrout a bathroom when the grout becomes unsightly, but since it is a tremendously big job, you naturally want the original grout to remain attractive for as long as possible.

Thanks jon-h!
I've done grout renovation once and would really like to avoid doing it again .
Will look for the "pearl effect" type next time...and will keep Mapei in mind
gaia

 

[jawen]

I don't know if I think the thread contributes much in general, but I'll respond a bit.

I didn't write that the seal is completely tight inward! I wrote almost tight!! significant difference.

Then when the seal catches the first splash of water, it "swells/expands" somewhat and becomes automatically a bit tighter. (just like all absorbent materials)

Then, I at least get tired of "these odd cases" that are constantly brought up in the thread as examples.
If you buy non-quality tiles from Bauhaus and the like, of course, they might be different sizes, not glazed over the edge, and in some cases even absorb water, etc., but my statements generally apply to professional use - consider all aspects, tile choice, seal choice, work method.

Then it is completely "abnormal" usage to stand and spray hot water directly on the wall, who does that in general?

ACME wrote.

"Seals are required to compensate for the tolerances that exist in all construction.
It is partly cosmetic and partly meant to provide a cleanable surface."

The dirt sticks precisely in the seal!! And if the seal is there to compensate for the tile's unevenness, then can you tell me what in the wall would absorb the movements without the tile cracking?
AcME also wrote:

"As Jon has already pointed out, you cannot generalize as you do - it varies between manufacturers. What they all do have in common is that they do not specify how thick the waterproof layer should be applied, but in how much quantity per sqm."

How dumb is that!! How much per sqm...
Yes, then you can just put a lump on one edge of each sqm, right?

Obviously, everything is based on thickness if one is to have a standard for things, the industry within galvanization on nails/iron etc. uses microns as thickness = the quality of the galvanization, in Epoxy/rust protection/paint/painting, etc., microns are also used.

Then, of course, it is unhealthy to have larger amounts of water standing on floors and walls, we use soap and shed cell residues/dirt when we shower, so obviously "a bit" of it goes in with the water and creates a breeding ground for various types of mold growth.

Even water alone contains bacteria that relatively quickly create bacterial growth, pour a glass and let it stand at room temperature for 5-6 days, then you can tell whether it looks good or smells nice.

Then there's talk about vapor-tightness and such, I get a bit tired then, of course, we should try to improve everything within construction and other things, but swallowing everything hook, line, and sinker often doesn't turn out well.

For example, more than 500,000 bathrooms just in Stockholm have managed very well for a long time despite the lack of moisture barriers on walls.
Of course, water usage was entirely different in the 30s-40s-50s, but already in the 60s we began using water on a larger scale.
Moisture can migrate through many constructions without causing problems and is naturally ventilated away, then if the building is made of wood, obviously, one should build accordingly.

But the current talk about bathroom regulations and BKR, I don't buy that; Germany has always had significant pressures regarding construction rules, so the large giants "buy" themselves industry regulations just as the oil industry buys electric car manufacturers, stalls solar panel development, etc.

For example, it became entirely forbidden to use any moisture barrier other than Oibit in 1991, all bathrooms of brick/plaster/stone, etc., had to use precisely Oibit, an entirely black mass somewhat like tar.

Then around 1993, when I had certainly done 200 bathrooms with just Oibit, it became completely forbidden to use the product.

But as far as bathroom regulations go, only the future will show what will apply; in my own case, if I need to build a bathroom, I will continue to use plasterboard and my "usual" approach and be careful with ventilation.

Then ACME asked what my role was in the approximately 2200 bathrooms.

In teams of 3, I have done complete plumbing replacements, i.e., demolished, plastered, rubbered, tiled, laid tile, installed sewage/water pipes/vvc, and installed appliances/hangers, i.e., all the tasks performed.
In almost all these cases, we have "offered/done free of charge" one or two large laundry rooms for the tenants.

I have probably been involved in some way in over 5000 bathrooms in total but only count those I have been 100% working on, i.e., done all the tasks.
We had just on S:T:eriksgatan in Stockholm 1480 bathrooms during 1991-1996, and then I have done the entire Garvargatan in Stockholm, 7-8 buildings in Sundbyberg/Solna, Utövägen/Skarpövägen in Orminge, etc.
Did my first plumbing replacement in 1987.
Also did about 50 villa bathrooms with JM AB, and outside of these, certainly done 30 more in private homes.

Best regards, Jawen