Why Does a Floor Drain Smell?

Why Does a Floor Drain Smell?

The Real Cause of Odor and the Permanent Solution

One of the most common problems in bathrooms, showers, balconies, and wet areas is bad odor coming from the floor drain. If the smell continues even after cleaning, the problem is not hygiene — it is the drain system itself.

In this article, we explain why floor drains smell and how our flap-equipped floor drains with S-trap design permanently prevent odor and insects.

Why Does a Floor Drain Smell?

1. No water trap (siphon)
Many standard floor drains do not have a siphon. Without a water barrier, sewer gases rise directly into the space.

2. The drain dries out
In rarely used bathrooms or balconies, the water inside the drain evaporates. Once the water is gone, odor starts immediately.

3. Waste buildup
Hair, soap residue, and organic waste can cause secondary odors, but this is not the main problem.

4. Wrong product selection
Visually nice but technically weak floor drains will always cause odor issues.

Temporary Solutions Do Not Work

  • Pouring bleach → Temporary

  • Using air fresheners → Only masks the smell

  • Pouring water regularly → Not permanent

???? Odor is a design problem, not a cleaning problem.

Permanent Solution: Flap Floor Drain + S-Trap Design

How Does the S-Trap Work?

An S-trap is a specially designed siphon where the internal channel is shaped like the letter “S”.

  • Water always remains in the curved section

  • This water creates a natural seal

  • Sewer odors and gases cannot pass

  • Insects and pests are blocked

???? The water inside the S-shaped trap is a permanent odor barrier.

What Does the Flap System Do?

Flap-equipped floor drains include a mechanical valve that:

  • Opens during water flow

  • Closes automatically afterward

This provides extra protection against:

  • Odors

  • Backflow

  • Insects and pests

Our Approach

We manufacture floor drains using:

  • S-trap technology

  • Flap (valve) system

This combination prevents odor before it starts, even in rarely used areas.

Conclusion

Floor drain odor is not inevitable.
With a properly designed S-trap + flap floor drain, odor and insects are permanently eliminated.