Washroom Odour Control in High-Footfall Buildings
You can mop a washroom ten times a day and still have people walk in and wrinkle their nose. In a busy mall, office tower, hospital, or airport, that smell does real damage. People judge the whole building by it.
As one CIJ article puts it, it doesn’t matter how well or how often a washroom is cleaned. If it smells bad, people will think it’s dirty.
The good news is that washroom odour has clear causes, and each one has a fix. This guide brings together what cleaning experts and facility teams have shared with Clean India Journal.
Why busy washrooms smell even after cleaning
Most washroom odour isn’t coming from the air. It’s coming from the surfaces and pipes.
Anil Sanghvi of Hygienetech India explains that the main sources are foul gases released through urinal drain lines and microbes feeding on dried urine in the grout around urinals. Together, they produce extremely foul odours, typically ammonia.
There are a few other common culprits:
- Uric acid crystals. These build up in drain pipes, cause odour, and block the pipes over time. In bad cases, the whole pipe has to be replaced.
- Grout. It’s often the most common cause of restroom odour, which is why floors need regular scrubbing, not just mopping.
- Dry traps. The S-trap in a toilet has two jobs. It stops what goes down from coming back up, and it controls odour. When a trap dries out, the smell comes straight up.
- How people use the washroom. At Mumbai airport, washrooms had air fresheners and auto-janitors but still smelled. Users often left seats and floors wet, and regular solutions struggled to keep up.
It’s one of the most common complaints
Odour isn’t a minor issue for users. In a poll of facility managers in commercial offices, urine odour and visibly dirty floors were among the five most common restroom complaints.
And the bar is high everywhere. CIJ has reported a 2025 international survey by Tork that found that only 20% of public restrooms worldwide meet users’ expectations for cleanliness and hygiene.
7 ways to control washroom odour in high-footfall buildings
1. Identify the odour before you treat it
The first step is to find out where the smell is actually coming from. Sometimes the fix is as simple as putting water back in the trap. Other times you may need drip systems in urinals, urinal mats or odour eliminators. Mr Sanghvi also points out that the right approach depends on how many urinals, western commodes and washbasins a washroom has. There’s no one-size-fits-all answer.
2. Eliminate odour, don’t mask it
The industry has moved on from simply covering up smells with fragrance. Enzyme-based, anion-based, and bio-based products are now designed to eliminate odour, not mask it. Odours should be broken down at their source. Remember that not every air freshener can break down uric acid crystals, which are the root cause of urine odour.
3. Treat the drains and urinals directly
Since so much odour comes from drain lines, treat them directly. An automatic toilet cleaner cum deodoriser can loosen hard deposits on surfaces and in the drain pipes below urinals. Biological urinal toss blocks can help clear blockages, which also reduces odour. Urinal screens catch debris like cigarettes and paper, and some fight odour between cleaning visits for up to 30 days.
4. Scrub floors and grout regularly
Mopping alone moves dirty water around the grout. Regular floor scrubbing keeps grout clean and odour away. In busy buildings, this means building deep cleaning into the schedule, not leaving it for special occasions. At Mumbai airport, each washroom is deep cleaned daily because of the footfall.
5. Consider waterless urinals
It sounds surprising, but water itself is one of the causes of urinal odour. When urine comes into contact with water, its urea is oxidised into ammonia, which is released into the air.
Waterless urinals avoid this. Most use a trap filled with a liquid sealant that stops odour escaping. Because they stay dry between uses, they’re also hostile to bacteria. The water savings are large too. One solution covered by CIJ saves at least 27,000 litres per urinal each year. Waterless, odourless urinal bowls are now marketed specifically for high-footfall public and commercial buildings.
6. Use odour neutralisers the right way
Odour neutralisers help a washroom keep that “just cleaned” feel long after the cleaner has left. In a JohnsonDiversey study covered by CIJ, people rated a washroom better when an odour neutraliser was added in a timed wall dispenser, even though the cleaning was exactly the same.
But a neutraliser is not a cleaner. Using it to wipe surfaces just makes a dirty washroom smell nice. Choose neutralisers that don’t irritate users, cause allergies or release VOCs.
7. Train your housekeeping team
Products only work if they’re used properly. Well-trained housekeeping staff, regular surface cleaning and periodic deep cleaning all help control odour. Teams should understand why each step matters, not just what to do.
Quick odour control checklist
| Problem | Likely cause | What to do |
| Smell near urinals | Drain gases, uric acid build-up | Drain treatment, urinal screens or toss blocks |
| Smell from floor | Dried urine in grout | Regular floor scrubbing and deep cleaning |
| Smell from drains | Dry trap | Refill traps; check drip systems |
| Smell returns soon after cleaning | Masking, not eliminating | Switch to enzyme or bio-based products |
| High water use plus odour | Flushed urinals | Consider waterless urinals |
The bottom line
In a high-footfall building, odour control isn’t about a stronger air freshener. It’s about finding the source, treating drains and grout, choosing products that eliminate rather than mask, and giving your team the time and training to do it well.
You can explore washroom hygiene and odour control solutions, including waterless urinal systems, from brands on CIJ Connect and enquire directly.
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