Drain channel vs. floor drain: what is better for a shower enclosure?
Linear drain vs. floor drain: what is really better for a shower area?
When deciding how to drain water from a shower area, you will sooner or later come across a crucial question: should I install a drain or is a classic floor drain sufficient? At first glance, it seems like a simple choice – after all, both drain water. The reality, however, is a bit more complicated and depends on much more than most people realize before starting the renovation. A wrong decision at this stage can cost you several extra hours of work, complicated slopes in the floor, or in the worst case, visible cuts in the tiling and standing puddles that simply won't disappear.
In practice, I have seen bathrooms where the owner invested in an expensive format tile only for the craftsman to later cut one tile in the middle of the beautiful surface just because the drain was forgotten to be planned in. I have also seen cases where someone installed a one-meter-long drain into a tiny 80 × 80 cm corner and the result looked structurally and aesthetically unfortunate. The goal of this article is to give you enough information to make the right decision even before you call the tiler.
Basic difference: what is a drain and what is a floor drain
A floor drain (also called a floor outlet or floor drain) is a point drainage solution. Water converges into one point – usually a square or round grid with dimensions from 10 × 10 cm to 15 × 15 cm – from which it flows away through a trap into the sewer. The entire shower floor must be sloped so that water flows precisely into this one point.
A linear drain is a linear (extended) drainage solution. Instead of one point, it collects water along its entire length – most commonly 60 to 120 cm. It can be placed along a wall (one-sided slope of the floor) or in the middle of the space (two-sided slope). A typical example is Flexible – Linear drain with edge for perforated grid and adjustable wall flange, length 850 mm, which is designed precisely for use along the wall of a shower area.
Floor slope: key technical parameter
This is the most important thing that most people underestimate. The standard STN EN 1253 recommends a minimum slope of 1.5 % for floors in wet areas, and in practice, 1.5 – 2 % is commonly used. For a 100 cm long space, this means a height difference of 15 – 20 mm. And it is precisely here that problems with the point drain begin.
If you have a drain in the center of an 80 × 80 cm corner, each corner of the floor must be shifted in height by 6 – 8 mm relative to the center. If you have a large shower area of 120 × 120 cm or a walk-in shower without a bathtub, the height difference in the corners can be 12 – 18 mm. This is easily achieved in a clean concrete base, but with large format tiles of 60 × 60 cm or 120 × 60 cm, it is a real challenge: the tile is larger than the slope, which means you either have to cut each tile into the shape of a trapezoid (practically impossible for an average tiler), or cut the tiles into smaller formats and solve the slope in a mosaic-like way. The result can be visually disturbing.
A linear drain along the wall elegantly bypasses this problem. The entire floor is sloped in one direction – from the far wall towards the drain. The slope is therefore uniform across the entire width of the area and even large format tiles of 120 × 60 cm lie without problems. For tiling where the optical line of the grout is important, this solution is significantly more advantageous.
Floor drain: when is it the right choice
I don't want to take a position that a floor drain is always worse – that would not be true. There are situations where a floor drain is not only sufficient, but directly optimal.
Small shower enclosures up to 90 × 90 cm
In compact showers with atypical shapes, corner solutions or preparations for a bathtub with a drain, a point drain fits perfectly. The area is small, the slope is easily achievable without visual compromises. A typical product is, for example, Floor drain with chrome grid 12 × 12 cm, DN 40, brass – a compact solution with a solid brass construction, chrome grid and DN 40 drain, which corresponds to the standard drain capacity in a household. If you are interested in what drain diameter is right for your situation, read the article What drain diameter do I need: DN32, DN40 or DN50? in the Knowledge Centre.
Existing sewage lines in the middle of the bathroom
If you are renovating a bathroom and the sewage connection is firmly fixed in the floor in the middle of the space, installing a trench would mean either a long drain line under the screed (increased thickness of concrete, problems with slopes) or retiling the entire floor. In such a case, a floor drain is simply more reasonable. Siphon accessories – including links to bathtub variants, such as Automatic bathtub siphon with overflow filling, chrome – can be found in the drainage technology category.
Shower tray with integrated drain
If you are installing a ready-made shower tray (acrylic, SMC or stone), it usually has its own drain, which works on the principle of a point drain. There is nothing to solve here – the drain is an integral part of the product.
Trench drain: when is it the right choice
Large walk-in showers and barrier-free solutions
This is the main domain of trench drains. If you are designing a shower without a bathtub, without a threshold, where the bathroom floor smoothly connects to the shower area, a linear trench is practically essential. It allows for the realization of a one-way slope across the entire area, while the visual transition from the bathroom floor to the shower remains almost invisible – especially if you use a trench with the same tiling material in the grid.
Large-format tiles and long tile lines
As we mentioned regarding slopes – if you are laying tiles 60 × 60 cm, 90 × 90 cm or even 120 × 120 cm, a point drain complicates the slope geometry. A trench along the wall allows you to maintain parallel grout lines with an even slope, which is not only more aesthetically clean, but also technically correct. Look for the article Installation of a floor trench step by step: slope, position, connection in the Knowledge Centre – you will find there a detailed procedure including the calculation of the screed thickness.
Family homes with two residents of different heights or barrier-free solutions
With a barrier-free bathroom, where the shower area is intended for an older or mobility-impaired user, a trench along the wall is a safer solution. The floor is flat, without any protrusions, the grid lies flush with the surface and a wheelchair or walking aid can pass without getting stuck. No "hill" towards the drain in the middle, which could cause someone to trip over.
Aesthetics and design
Modern trenches also offer decorative grids – perforated stainless steel, tile grid (so-called tile insert), where you insert the same tile as on the floor into the grid, making the trench almost invisible. This is not comparable to a point drain – the grid is always quite noticeable, even if it is chrome. Aesthetically clean solutions such as double-sided floor trench, 750 mm, DOUBLE9 FIT and GO, stainless steel offer a professional result with a perfect line.
Technical parameters to compare
Drain capacity
A standard home shower produces 8 – 15 liters of water per minute. A point drain DN 40 can handle 20 – 30 l/min with a proper siphon, which is sufficient for home use. A linear trench with a larger catchment area and DN 50 drain can handle 30 – 50 l/min. The practical difference during normal showering is negligible, but with a high-flow rain shower head or a steam shower, the capacity of the trench can be an advantage. More about drain diameters can be found in the article What drain diameter do I need: DN32, DN40 or DN50?
Installation depth
This is one of the most common reasons why a trench does not work in a renovation. A linear trench requires a certain structural height – typically 90 – 120 mm from the top edge of the grid to the lower edge of the drain neck. Add a siphon with a water seal (another 40 – 80 mm) and compare the resulting depth with how much thickness you have available in the floor.
In panel buildings with concrete ceilings, this depth is limited and can be problematic. There are, however, shallow trenches (so-called slim) with a structural height from 65 mm, but you always have to check and consult with a tradesperson before buying. On the other hand, a point drain DN 40 with a flat siphon can have a structural height from 50 mm, which is significantly less space demanding.
Cleaning and maintenance
Here the trench has an advantage. The grid is lifted as a whole, usually without tools, the cleaning space is more spacious and hair, soap residue and deposits are easier to remove. The water seal (siphon) of modern trenches is accessible directly from above after removing the grid.
A drain with a chrome grid has a smaller access opening – the grid has to be unscrewed or removed, cleaning is only possible with a wire or a kitchen spatula. With neglected maintenance, clogging and bad odors occur more quickly. If you are troubled by bad smells or standing water, we also recommend reading the article Siphon smells or water stands: causes and solutions and How to clean a clogged siphon without chemicals in our Knowledge Centre.
Price
A point drain is cheaper – in the category of standard brass or stainless steel models we are talking about 10 – 40 EUR per piece. A linear drain is more expensive: high-quality stainless steel models of 850 mm range from 60 to 200 EUR depending on the design, depth and material quality. Installation costs must also be added, which are somewhat more demanding for a drain.
However – and this is a crucial argument from practice – if you have to redo the slopes, have new tiles laid or repeatedly call a tradesperson due to a poor choice of drainage solution, the price of the "cheap" drain will increase by hundreds of euros. Choosing the right solution from the beginning is always cheaper.
Adjustable flange: why it matters
When installing a drain along the wall, one of the most important structural details is the adjustable flange – that is, the sealing element that fills the gap between the drain body and the wall. Since the wall is never perfectly flat and vertical and the drain has a fixed body width, without an adjustable flange a gap would form through which water would seep under the tiles and into the screed.
The adjustable flange slides along the horizontal axis and allows for compensation of wall deviations of ±10 mm without the need to grind or pad the drain body. It is a detail, but during the renovation of older bathrooms, where walls are often deviated from the vertical plane by 5 – 15 mm, it is a life-saver. More on this topic can be found in the article Adjustable flange for floor drains: when do I need it and how does it work? in the Knowledge Centre.
Material: stainless steel, brass or plastic?
Stainless steel is dominant for drains – the reasons are corrosion resistance, mechanical strength and aesthetic cleanliness. Stainless steel AISI 304 is the standard for interior use, AISI 316 (marine grade) is used for exterior or industrial applications. For home use, AISI 304 is more than sufficient.
For point drains, brass with chrome finish is popular – it is heavier, more mechanically durable and the chrome layer prevents limescale and soap scum from sticking as much as on a plastic surface. Plastic (ABS or PP) is used more in cabinet traps and hidden piping, where it is not exposed to view or mechanical load. More on the comparison of materials can be found in the article Stainless steel, brass or plastic: which material to choose for bathroom drainage?
Concrete scenarios from practice: what works and what doesn't
Scenario 1: Panel apartment, bathroom 180 × 220 cm, tile 30 × 60 cm
In this case, the thickness of the floor construction is limited – usually 80 – 100 mm from the surface of the old screed. If you want a drain, you have to remove the old screed, lower the floor or use a slim drain. If the shower area is only 80 × 80 cm with a prefabricated bathtub, a point drain is the clear choice here. If you plan the entire bathroom floor in the same tile with a shower corner without a bathtub, consider a slim drain along the wall – the investment is visually worth it.
Scenario 2: New family house construction, bathroom 3 × 3 m, shower 120 × 120 cm
Here there is space, screed thickness, and flexibility. If the architect and designer are working with large-format tiles 60 × 120 cm and a walk-in shower without a bathtub, a wall-mounted drain is a professional recommendation. A one-way slope is feasible, the aesthetics are clean, and the space feels airy. The sewer connection is planned under the wall, not in the center of the room.
Scenario 3: Renovation of an old core, bathroom 90 × 90 cm, low ceiling, old piping
A classic Slovak panel apartment with a core – the standard core has the sewerage fixed in the shaft along the wall, and the floor has a preparation at a specific location. The options are limited, and rerouting the drain is a risky operation. Here, a point drain with a brass body and chrome grid DN 40 is the correct and pragmatic solution. The result is functional, clean and long-term reliable.
Scenario 4: Barrier-free bathroom for an elderly parent
Step-free shower, floor at the same level as the bathroom, slope towards the wall. A wall-mounted drain is the most suitable here in terms of safety (no raised areas), hygiene (easier cleaning) and aesthetics (smooth floor). Combine it with a seat and grab bars for a complete barrier-free solution.
Installation tips: what to think about before ordering
- Location of the sewer connection: Before ordering a drain or a point drain, measure exactly where the sewer connection comes out of the floor or wall and what its height is. The drain must be connected to the sewer with sufficient slope of at least 1 % (recommended 2 %) from the drain towards the sewer.
- Construction height: Measure the available depth – from the finished floor down. Do not forget the layer of waterproofing (2 – 5 mm), adhesive (5 – 10 mm) and tiles (8 – 12 mm). The drain must be at the correct height before the screed is poured.
- Waterproofing: The drain or point drain does not replace floor waterproofing. Always apply waterproofing under the tiles first, then embed the edge of the drain into the waterproofing. Manufacturers supply sealing tape or flange exactly for this purpose.
- Drain length: The drain should be at least as long as the width of the shower area – ideally 10 – 20 % longer, to catch water reflected from the walls. Standard lengths: 600, 700, 750, 800, 850, 900, 1000 mm.
- Grid: The grid must be the same length as the channel. Buy them together as a set, or check compatibility. A perforated grid is the most universal, a tile insert grid is the most elegant, but requires custom tiles.
Comparative overview table
| Parameter | Point drain | Linear drain |
|---|---|---|
| Floor slope | 4-way (more demanding) | 1-way (simpler) |
| Large-format tiling | Problematic | Suitable |
| Construction height | from 50 mm | from 65–90 mm |
| Barrier-free solution | Conditionally | Ideal |
| Cleaning | More demanding | Simpler |
| Price (approximate) | 10–40 EUR | 60–200 EUR |
| Installation complexity | Lower | Higher |
| Drain capacity | DN40: ~25 l/min | DN50: ~45 l/min |
| Aesthetics (design) | Standard | Modern, variable |
| Suitability for small corners | Excellent | Limited |
Most frequently asked questions (FAQ)
Can I install a floor drain in an existing shower with a bathtub?
Technically yes, but practically it is a major renovation. You will need to remove the bathtub, grind or excavate the mortar, lay new waterproofing and slope layers, and install the drain before laying the new tiles. If you are planning such a renovation, expect a full renovation of the entire shower area – it is not a one-hour job. In this case, it is also an ideal opportunity to switch to a step-free walk-in solution.
What is the minimum floor thickness for a linear drain?
It depends on the specific model. Standard drains require 90 – 120 mm from the top edge of the grid to the bottom of the drain opening. Slim versions can manage 65 – 80 mm. Always add the thickness of the tiles (8 – 12 mm) and adhesive (5 – 8 mm) to this. Always check the construction (installation) height of the specific model in the product technical sheet before purchasing.
Is a wall-side drain or a central double-sided drain in the middle of the shower better?
It depends on the layout. A wall-side drain (one-way slope) is suitable if you want to maintain parallel tile lines without visually dividing the area and if the sewage connection runs along the wall. A central double-sided drain – such as DOUBLE9 FIT and GO – is a solution for larger walk-in showers or situations where you want the drain to be visibly in the center of the space as a design element. It requires a symmetrical slope from both sides.
Can the floor drain be placed in a different location than the center of the shower area?
Yes – the drain can be placed in a corner, next to the wall, or anywhere the sewage allows. The key is that the entire floor must slope toward it. A corner or wall-adjacent drain simplifies the slope similarly to a drain (the floor slopes in two directions instead of four), which can be a compromise solution in limited space and with an existing layout.
What is a water seal and why is it important for drains and floor drains?
A water seal (trap) is a water reservoir in the outlet that prevents sewer odors from entering the bathroom. Every drain and floor drain must have its own water seal. In bathrooms where the shower is used infrequently (e.g., a guest bathroom), the water in the trap can dry out – the result is an unpleasant smell. The solution is dry (mechanical) seals or regular water refilling. More information can be found in the articles Smells from the trap or standing water: causes and solutions and How to choose the right trap: sink, bathtub or shower?
Do the same waterproofing requirements apply to drains and floor drains?
Yes, the same principle applies to both: waterproofing must cover the entire floor of the shower area and must extend up the walls at least 15 – 20 cm above the floor; for showers without a bathtub, the recommended height is 100 – 150 cm. The edge of the drain or drain must be integrated into the waterproofing using a sealing gasket or butyl rubber tape – manufacturers usually provide or offer these elements as accessories. Neglecting waterproofing is the most common cause of moisture problems in bathrooms, regardless of the type of drainage element.
Conclusion: how to make the right decision
If I were to summarize it into a practical guide: for compact showers up to 90 × 90 cm, renovations with limited floor thickness, or existing sewage connections in the center of the room, choose a point drain – it is reliable, cost-effective, and functional. For large walk-in showers, large-format tiles, barrier-free solutions, or new constructions where you have full design freedom, a wall-side floor drain is a significantly better choice in terms of technical, aesthetic, and usability aspects.
Deciding on drainage is not a matter of fashion – it is a technical decision that will affect daily comfort, easy cleaning, and the long-term durability of the entire bathroom solution. Invest time in making the right choice before starting the work and you will save yourself from complications I have repeatedly seen with customers who made last-minute decisions or chose based on what was "cheaper in stock".
If you want to learn more about specific products, visit the Drainage Technology category on atria.sk, where you will find a complete range of drains, drains, traps, and accessories. Further technical topics – including articles on bathtub traps such as Bathtub Trap CLICK/CLACK with removable outlet – can be found directly in the Knowledge Center of this category.
Do you have a question on this topic?
Having trouble deciding or dealing with a specific situation in your home? Write to us – we are happy to help.