Differences between Renovmodul, Jadromodul, and Sadromodul – which type is suitable for your bathroom?
Renovmodul, Jadromodul, and Sádromodul – Three Systems, One Purpose, But Fundamental Differences
When a customer first comes into the showroom and says they want "that wall-mounted toilet," they usually have no idea that behind the term "wall-mounted installation system" lie three fundamentally different products that differ not only in price, but primarily in the installation method, the type of building structure into which they fit, and their long-term reliability under specific conditions. A customer who buys a Sádromodul and wants to embed it into a brick partition is making the same mistake as the one who buys a Renovmodul and tries to nail it into a drywall wall. The result is the same in both cases – a problem, a complaint, and a redo.
This article is therefore dedicated to one single goal: to help you understand what Renovmodul is, what Jadromodul is, and what Sádromodul is, how they differ, why these differences exist, and how to correctly choose the right variant for a specific situation – whether you are renovating an old panel apartment, building a new family house, or renovating a bathroom in a brick house from the 1970s.
What All Three Systems Have in Common
Before we get into the differences, it is useful to understand what is common to all three – because the foundation is the same. Every wall-mounted installation system is essentially a load-bearing steel or galvanized structure, into which a flushed cistern (so-called underfloor cistern), water and waste pipe connections, and mounting points for the suspended toilet are integrated. The toilet bowl is hung on the system using screws and extended threaded rods, the flushed cistern is hidden in the structure, and the operation takes place via a control button on the front side. The result is therefore visually the same: a clean, modern suspended toilet without visible pipes and without the classic cistern on the toilet.
All three types – Renovmodul, Jadromodul, and Sádromodul – are also available in a version with a tablet dispenser for the toilet. This feature allows automatic dispensing of cleaning and hygiene tablets directly into the cistern with every flush. If this topic interests you in more detail, in the Knowledge Center section you will find a separate article Tablet dispenser in wall-mounted systems – how it works and why to use it, where the whole mechanism is explained step by step.
A common denominator is also the height adjustment: all systems offer adjustable height within a range that allows adaptation to different floor heights after tiling, bowl height, and personal user preferences. This topic is covered in the article Dimensions and height adjustment of wall-mounted systems for suspended toilets.
Renovmodul – The Classic for Masonry Partitions and Embedding
Renovmodul is the oldest and most robust construction among the three types. Its name clearly states: it is intended for installation where the entire system will be enclosed in masonry – that is, embedded. It is used where the wall is made of brick, aerated concrete, or concrete construction, or where a new masonry partition is built specifically for this purpose as part of the renovation.
The Renovmodul construction is designed to withstand the pressure of plaster and masonry materials, to be rigid, and to be easily tiled with ceramic tiles after embedding. The frame is usually made of steel profiles connected by rigid anchoring elements and offers access to water and waste pipes from the side or from below according to the configuration of the bathroom.
A typical situation from practice: an older panel apartment with original cast iron waste and copper supply lines. The customer wants to modernize the bathroom, knock down the old toilet cabin, create an open layout, and install a suspended toilet. The mason builds a new brick partition, installs the Renovmodul into it, the embedding is carried out with classic masonry mortar, then tiling follows, and finally the toilet bowl is hung. This procedure is proven, has been working for decades, and is known to almost all masons and plumbers of the older generation.
It is important that after embedding, access to the inspection elements must be preserved – primarily to the safety valve and the filling valve of the cistern. This is ensured by an inspection opening, which must be properly dimensioned and accessible even after tiling. This issue is further addressed in the article Common faults of wall-mounted installation systems and how to repair them, where situations are described in which inaccessible inspection becomes a real problem.
Advantages and Limitations of Renovmodul
The main advantage of Renovmodul is the mechanical strength after embedding. The entire structure is literally part of the wall, which eliminates vibrations, noises from flushing, and long-term movements of the load-bearing structure. The disadvantage is that the installation takes longer – the mason, plumber, and tiler must coordinate their work, because the Renovmodul must be first embedded, then plastered or prepared for tiling, and finally tiled. Repairs after embedding are also more difficult – that is why it is important to install the system correctly from the beginning and with a sufficiently dimensioned inspection flap.
Core Module – Dry Installation Specifically for Apartment Cores
The apartment core is a phenomenon of socialist panel construction. It is a prefabricated bathroom cell made of pressed wood fiber or laminated panels, which was installed as a whole directly during the production of panel apartments. These cores have thin walls (usually 40–80 mm), are not able to carry standard masonry loads and do not react well to moisture associated with plaster or sealants.
Core Module is designed precisely for this type of construction. It is a dry installation system – that is, without masonry, without plaster, without wet processes. The load-bearing structure is anchored into the floor and ceiling (or into existing load-bearing elements of the apartment core) and panels made of fiber cement boards, drywall or special moisture-resistant materials are then attached to it, forming a "new wall" in front of the original wall of the apartment core.
Typical practical situation: renovation of an apartment in a panel building from 1978. The original bathroom has a plastic apartment core with a standing WC, the customer wants modernization to a wall-hung WC, but the walls are only 60 mm thick wood fiber. Masonry solution (Renovmodule) is not an option – the wall is too thin and unsuitable in terms of material. A drywall solution (Drywall Module) is also not ideal, because the apartment core has specific dimensions and solid anchoring from floor to ceiling is required. Here, the right choice is the Core Module.
Why Core Module cannot be replaced by Drywall Module
At first glance, Core Module and Drywall Module may seem the same, as both are intended for dry installation. The difference, however, lies in the method and strength of anchoring and in the overall rigidity of the load-bearing structure. Apartment cores usually have a height of 2100–2350 mm and the Core Module structure is designed to use anchoring from floor to ceiling as the basic stabilizing element. A drywall system (Drywall Module) assumes that primary anchoring is into the floor and secondary into the drywall profile, which is not sufficient in the case of a thin apartment core – the entire front wall could move and under load (e.g., when someone sits on the edge of the WC bowl), the whole structure could gradually lose stability.
Practically this means: if you have a panel apartment with an original apartment core, always choose the Core Module. More about the installation process itself can be found in the article Installation of the front wall system when embedded into apartment core.
Drywall Module – for dry construction and modern drywall structures
Drywall Module is intended for modern construction methods, where bathroom walls are solved by drywall dry construction. It is a common procedure in new single-family homes, as well as in apartment renovations, where the investor decides not to use masonry and to build the entire bathroom as a light dry structure on aluminum or galvanized profiles covered with water-resistant drywall (marked as GKFi or GKFI according to the standard, or with a special cement-fiber cladding material).
Drywall Module has a load-bearing frame designed to be easily integrated into the system of drywall profiles (standard CW and UW profiles of 75 or 100 mm width). Anchoring is primarily into the floor and floor UW profile, with the structure itself forming a rigid whole. The front side of the module is covered with drywall just like the rest of the wall, resulting in a perfectly flat and visually uniform surface ready for cladding.
Typical practical situation: new construction of a single-family home, the investor wants a modern solution for the entire bathroom as a "white box" without masonry. The drywall contractor builds the entire bathroom including the front wall for the WC system using dry assembly. The Drywall Module is inserted into the load-bearing profile, water and waste connections are connected before cladding, then the structure is covered with drywall, tiled and the WC bowl is hung. The whole process is faster than with the Renovmodule, does not require wet processes and the bathroom can be completed without waiting for the plaster to dry.
Important Limitations of the Gypsum Module: Load Capacity and Humidity
The gypsum board false wall has its limits. A bathroom is a humidity-stressed environment, so it is essential to use only moisture-resistant gypsum board (green board, class H2 or H3 according to EN 520) or cement fiber boards. Standard gypsum board (white board) does not belong in a bathroom. This condition applies to the entire cladding, not just the part behind the Gypsum Module.
The load capacity of the WC bowl suspension on the Gypsum Module is dimensioned the same as for other systems at 400 kg – which is a normative value that must be met. However, this load is carried by the metal frame of the module itself, not by the gypsum board. The gypsum board serves only as a covering and aesthetic layer, so you must not consider it as a load-bearing structure during WC installation.
Comparison Table: Renovmodul vs. Jadromodul vs. Gypsum Module
| Parameter | Renovmodul | Jadromodul | Gypsum Module |
|---|---|---|---|
| Type of installation | Built-in | Dry assembly | Dry assembly |
| Type of construction | Brick, aerated concrete, concrete | Panel apartment core | Gypsum board false wall |
| Wet processes | Yes (mortar, plaster) | No | No |
| Typical use | Old panel building, brick house, reconstruction | Panel apartment, core renovation | New construction, dry false wall |
| Installation speed | Slow (waiting for curing) | Medium | Fast |
| Noise after installation | Lowest | Medium | Medium |
| Accessibility for inspection | Through inspection opening | Through panel | Through inspection opening in Gypsum |
| Coordination of trades | Bricklayer + plumber + tiler | Plumber + gypsum boarder | Gypsum boarder + plumber |
Noise from flushing: how the type of system affects acoustic comfort
This is a topic that customers often underestimate and only realize when the false wall is finished and built in. The acoustic comfort of a suspended WC depends on several factors: the quality of the seals of the cistern itself, the materials surrounding the system, and how tightly or loosely the construction is anchored in the surrounding environment.
The Renovmodul built into solid masonry has the best sound insulation – the mortar and brick material around the system dampen the vibrations caused by flushing and filling the cistern. The Jadromodul and Gypsum Module in dry construction transmit vibrations more easily because the free space between the load-bearing frame and the covering panel can act as a resonant cavity. For this reason, it is recommended to fill the cavities behind the panel with mineral wool that absorbs the sound during dry installation. This detail is sometimes omitted in dry walling projects, and the customer then hears every flush from the adjacent room.
Choosing a WC seat for the false wall system
The choice of false wall system directly influences the choice of WC bowl and seat. There are several types of seats for WC bowls designed for false wall systems, and the mounting depends on the spacing of the fastening points on the bowl itself. For standard suspended WC, we recommend looking at WC seat SOFTCLOSE Duroplast, which closes slowly and eliminates loud slamming – a welcome feature if the bathroom is near the bedroom. For those who prefer flexible spacing, a good choice is universal WC seat with integrated insert Duroplast, which fits a wide range of WC bowls regardless of the specific spacing. Details on choosing a seat can be found in the article How to choose the right WC seat for the false wall system: Softclose, Duroplast, universal.
Control button – common for all three types, but with optional choices
One of the common "backdoors" in selection is the control button for flushing. All three types of false wall systems – Renovmodul, Jadromodul, and Gypsum Module – are compatible with the same range of control buttons, as the underfloor cistern is essentially the same. This means you can choose a button according to the aesthetics of the bathroom – chrome, matte black, white, with various shapes and sizes – and it does not matter which type of false wall system you have used. We deal with this topic in detail in the article Control buttons for flushing: how to choose the right type and color for the false wall cistern.
Reconstruction versus new construction: how the type of project determines the system selection
In practice, there is one simple rule of thumb: the type of pre-wall system is determined more by the building situation than by personal preference. A customer cannot just choose to "want Renovmodul because it is cheaper and faster" – if the wall is made of brick, the only option is Renovmodul. Conversely, a customer with a new construction and a dry building system would be inefficient to build a special masonry partition just to use Renovmodul.
Renovations of older apartments and houses mostly lead to the use of Renovmodul (if it is a brick or concrete wall) or Jadromodul (if it is a panel apartment with a bathroom core). New constructions of houses and apartments with modern lightweight construction use Sadromodul. In practice, we occasionally encounter combined projects – for example, an older panel apartment where the bathroom core is demolished and replaced with a dry construction. In such a case, Jadromodul becomes Sadromodul, because the new structure is made of drywall and not the original core.
Tablet dispenser – a function common to all three systems
All three pre-wall systems available at atria.sk – Renovmodul, Jadromodul and Sadromodul – are available in a version with a WC tablet dispenser. This dispenser is integrated directly into the cistern and, with each flush, releases a microdose of cleaning or disinfecting tablet into the water. The result is a cleaner toilet bowl, lower consumption of cleaning agents and longer intervals between cleanings.
The dispenser is a standard preferred option if the toilet is used intensively (large family, commercial space), or if the customer is allergic to common chemical cleaning agents and prefers controlled dosing. The entire mechanism of the dispenser function and the selection of suitable tablets are described in a separate article Tablet dispenser in pre-wall systems – how it works and why to use it.
Practical installation details and what to watch out for
Regardless of the type of system, there are some common rules that we know from practice to quickly become problems if set incorrectly:
- Height adjustment: All three systems offer adjustable height in the range of 980–1130 mm (for standard suspended WC bowls). The height is adjusted before final fixing and must take into account the thickness of the floor covering including tiling. If the plumber forgets the thickness of the tiles (usually 8–12 mm + adhesive), the WC bowl will be lower than planned.
- Level and verticality: The frame must be perfectly vertical and level, otherwise problems with aligning the seat will appear during installation of the WC bowl and the entire aesthetic effect will be lost.
- Inspection openings: For Renovmodul and Sadromodul, it is mandatory to leave an inspection opening to the safety valves and filling valve. The minimum recommended size of the inspection opening is 200×200 mm, a better standard is 300×200 mm.
- Waste connection: The waste pipe from the pre-wall system must be laid with a slope of at least 1–2 % towards the waste trap. With a smaller slope, insufficient drainage and sedimentation may occur.
- Sealing and hoses: For dry installation (Jadromodul, Sadromodul), it is important that all connections are properly sealed before closing the panel – after installation, no connection behind the load-bearing frame is easily accessible.
For a comprehensive view of the entire installation process from start to finish, we also recommend reading the article Installation of a pre-wall system into drywall step by step, where the entire process is documented in detail with all the intermediate steps.
Most common mistakes when choosing a pre-wall system from practice
The same mistakes repeat from customer experience, leading to complaints, rework and unnecessary costs:
- Purchase of Sadromodul into masonry: The customer or builder buys Sadromodul as "cheaper and modern", but has a brick wall. The problem arises during fixing – the drywall system is not intended for embedding and the steel frame without access to the masonry cannot be properly fixed.
- Purchase of Renovmodul into a bathroom core: Embedding Renovmodul into a thin chipboard wall of a bathroom core leads to cracking, loosening of the fixing and in the extreme case to shifting of the entire system under load.
- Forgetting about inspection openings: The tiler covers the entire surface with tiles, including the place where the inspection opening should be. After two years, the filling valve breaks down and the entire tiling has to be broken.
- Wrong height before tiling: The system is set to the final height without considering the thickness of the tiles. After tiling, the WC is too low or does not fit properly to the wall.
- Dry installation without mineral wool: The cavity behind the panel in Jadromodul or Sadromodul is not filled, resulting in acoustic resonance with each flush.
Frequently asked questions (FAQ)
Can I use Sadromodul if I have a brick wall in the bathroom, but I plan to build a drywall partition in front of it?
Yes, in this case Sadromodul is the right choice. It is not the material behind the partition that matters, but into which structure the system is fixed and clad. If you build a partition made of drywall profiles and sheets in front of the brick wall, Sadromodul integrates into this new dry construction. The brick in the background is irrelevant – Sadromodul is fixed into the floor and ceiling profiles of the dry partition, not into the masonry.
Is Jadromodul compatible with a bathroom core from the 70s without demolishing the original walls?
Yes, Jadromodul is designed precisely for this case. It is installed in front of the existing wall of the bathroom core (without demolition) and fixed to the floor and ceiling. The original walls of the core serve only as a background surface, not as a load-bearing element. After installation, the system is clad with water-resistant material and tiled, so the resulting bathroom looks modern despite the original construction behind the partition.
What is the difference in noise between Renovmodul and Sadromodul during a flush?
Renovmodul embedded in solid masonry is significantly quieter, because the mortar and brick material dampen the vibrations of the load-bearing structure and the water flow itself. Sadromodul in a dry structure without acoustic filling can be audible through the wall. The solution is simple: before closing the partition, fill the cavities behind the load-bearing frame with mineral wool with a density of at least 40 kg/m³. This simple step reduces noise by 8–12 dB.
Can I buy a pre-wall system without a tablet dispenser if I don't want it?
Yes, pre-wall systems are available in both versions – with and without a dispenser. The version with a tablet dispenser is usually only slightly more expensive and the dispenser can be left unnoticed if you do not want to use the tablets. Conversely, if you buy a system without a dispenser and later change your mind, the dispenser cannot be installed into the cistern without dismantling the partition.
What is the maximum load that a suspended WC on a pre-wall system can withstand?
All standardized pre-wall systems must withstand a static load of 400 kg at the fixing points of the WC bowl according to the European standard EN 15241. This load is carried by the steel load-bearing frame of the system, not by the drywall or masonry material around it. In practice, a suspended WC on a pre-wall system is therefore more stable than a classic standing toilet on the floor when installed correctly.
Can I later replace the flush control button on Jadromodul?
Yes, and without demolition or major interventions. The flush control button is standard removable and replaceable. The button is pressed into the frame in the front wall of the partition and held by a snap or screws depending on the type. For replacement, it is enough to remove the button, connect the new one and insert it back. The condition is that the new button is compatible with the specific cistern – manufacturers usually list compatibility in the technical data sheet of the product. We deal with this issue in the article Flush control buttons: how to choose the right type and color for your pre-wall cistern.
Conclusion: the right system = fewer problems for years to come
Choosing between the Renovmodule, Coremodule and Sádrmodule is not a matter of taste or price category – it is a technical decision that will
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