How to Get Rid of Persistent Washroom Odours

Why do washroom odours keep coming back?

A washroom can look clean and still smell unpleasant because many odour sources are not on obvious surfaces. They may sit in grout, floor edges, urinal surrounds, drains, sanitary bins, overflows, poorly ventilated corners or damp areas.

A peer-reviewed toilet hygiene review notes that biofilm build-up within toilet bowls, urinals and sinks can contribute to the persistence of pathogens and odours. That is why repeated surface cleaning may only provide a short-term improvement if the deeper source is still present.

• Urine residue around toilets, urinals, flooring, grout and splash zones.
• Biofilm inside toilet bowls, urinals, sinks and drains.
• Dry traps or plumbing faults allowing sewer gas into the room.
• Poor airflow or extract ventilation.
• Damp, mould or excess humidity.
• Waste bins, sanitary disposal units or nappy-changing waste.
• Cleaning products or air fresheners that mask odour rather than removing it.
• Cleaning schedules that do not match footfall or peak usage.

Start by diagnosing the type of smell

Different odours point to different problems. Before adding stronger fragrance, use the smell as a clue.

A sewage-type smell should be treated differently from a general stale odour. EPA school indoor air quality guidance identifies dry drain traps and sewer-gas pathways as building odour issues that need source correction, not perfume.

1. Remove the source before adding fragrance

The first mistake many facilities make is trying to overpower a bad smell with a stronger scent. That may temporarily change how the washroom smells, but it does not solve the reason the odour is there.

Start with a source check. In a commercial washroom, once-a-day cleaning may not be enough during peak periods. A pub, gym, shopping centre, petrol station, school, office or venue washroom may need scheduled checks, targeted spot cleaning and deeper periodic cleans focused on odour sources.

• The base of toilets.
• Urinal surrounds and splash zones.
• Grout lines and floor edges.
• Behind and below sanitary bins.
• Sink overflows and plugholes.
• Floor drains.
• Toilet brush holders.
• Mop buckets, cloths and cleaning equipment.
• Corners where moisture or residue collects.
• Nappy-changing or hygiene disposal areas.

2. Treat urine smells at floor level

Urine odours are one of the most common causes of persistent washroom complaints. The problem is rarely just inside the toilet or urinal. It is often around the fixture.

Standard mopping can spread residue if the cleaning solution, contact time or mop hygiene is poor. For persistent urine odour, the aim is to remove residue from the material it has soaked into, not simply wipe the surface.

Where flooring, grout or sealant has absorbed odour over time, deeper cleaning or replacement may be needed. For commercial sites, also review urinal flush settings, floor condition, cleaning logs and whether the washroom layout creates splash or pooling problems.

• Floor grout near urinals.
• The base and rear of toilets.
• Wall panels or partitions next to urinals.
• Flooring seams.
• Silicone edges.
• Corners that mops miss.
• Splashback zones.

3. Check drains, traps and plumbing

A rotten egg, sewer or sulphur-like smell often points to a drain or plumbing issue. In these cases, fragrance will not fix the problem.

Running water through a rarely used drain may restore the water seal in simple cases. If the smell persists, becomes stronger, or appears suddenly across multiple fixtures, it should be investigated by a qualified plumber or facilities professional.

• A floor drain has dried out.
• A sink or floor drain is rarely used.
• There is debris or biofilm inside the drain.
• A trap is damaged or not holding water.
• A plumbing vent is blocked or poorly positioned.
• Odour is being pulled into the room by airflow or ventilation.

4. Improve ventilation and air movement

Poor ventilation allows odours, humidity and airborne pollutants to linger. This is especially common in basement washrooms, older buildings, enclosed cubicles, busy hospitality venues and high-footfall public toilets.

UK HSE guidance says workplace toilet and washing facilities should include clean facilities that are well lit and ventilated. UK Building Regulations guidance separates Approved Document F ventilation requirements for dwellings and non-domestic buildings, with Volume 2 applying to buildings other than dwellings.

Ventilation does not replace cleaning, but it helps stop odours from concentrating. If a washroom always smells stale despite cleaning, airflow should be checked before adding more fragrance.

• Is the extractor fan working?
• Are vents blocked by dust, decor or storage?
• Does the smell worsen at busy times?
• Does the room feel humid or stale?
• Are doors or partitions stopping airflow?
• Is the washroom under negative or positive pressure?
• Does odour escape into corridors or customer areas?

5. Control moisture and damp smells

Musty odours usually come from moisture. Damp areas create the conditions for mould, bacteria and stale air. Even a small leak under a sink or persistent condensation around an extractor can create an unpleasant smell.

Indoor air guidance from the U.S. Consumer Product Safety Commission and EPA explains that inadequate ventilation can increase indoor pollutant levels because it does not bring in enough outdoor air to dilute emissions or carry indoor pollutants out. It also notes that high temperature and humidity can increase concentrations of some pollutants.

For commercial washrooms, moisture control may mean improving ventilation, fixing leaks, adjusting cleaning methods, reducing standing water and ensuring floors dry properly between cleaning rounds.

• Under basins and pipework.
• Ceiling tiles.
• Extractor vents.
• Behind toilets.
• Wall corners.
• Storage cupboards.
• Flooring that remains wet after cleaning.
• Areas around hand dryers or sinks where water splashes.

6. Avoid relying only on aerosols or heavy fragrance

Fragrance can improve the final impression of a clean washroom, but it should not be the main odour-control method. Heavy perfume over a bad smell often creates a worse experience: users can still detect the odour underneath, and the room feels artificially scented rather than clean.

Some air fresheners and fragranced cleaning products can also contribute to indoor air pollution. California Air Resources Board guidance explains that cleaning products and air fresheners can emit VOCs, and CARB maintains consumer product rules for several air freshener categories.

That does not mean scent should never be used. It means scent should come last, after the source has been treated and airflow is managed.

• Remove the source.
• Clean and maintain problem areas.
• Improve ventilation.
• Filter or treat the air where needed.
• Use controlled fragrance only if appropriate.

7. Use filtration where odours return between cleans

Some washrooms smell fresh immediately after cleaning but deteriorate quickly. This is common in high-footfall environments where the room is used continuously and the air never fully recovers.

Activated carbon is commonly used for gases and odours. EPA guidance says that to filter gases, an air cleaner should use activated carbon or another filter designed to remove gases, and that activated carbon can be effective where there is enough material in the filter.

California Air Resources Board guidance similarly notes that HEPA filters are useful for particles but do not remove gases, while activated charcoal filters can help remove certain gaseous pollutants and odours when properly designed and maintained.

For washrooms, filtration is best used as part of a wider strategy, not as a shortcut around cleaning or maintenance.

Where EcoBreeze fits into washroom odour control

EcoBreeze is designed for commercial spaces where odours return between cleans, especially washrooms and high-traffic environments. It should be seen as part of a complete odour-control plan: cleaning, maintenance and ventilation still matter.

Every EcoBreeze draws room air through an electrostatic mesh prefilter that captures larger airborne particles, hair and lint before honeycomb activated-carbon media adsorbs suitable gaseous odour compounds and VOCs. EcoBreeze provides controlled fragrance where selected; EcoBreeze Smart adds connected visibility and reporting; EcoBreeze Pure provides the same two-stage filtration pathway without added fragrance.

EcoBreeze is not an air conditioning, HVAC or ventilation system. It does not cool, heat or supply outdoor air. It is a commercial aircare system using an electrostatic mesh prefilter followed by activated-carbon gas-phase filtration, with fragrance determined by product route.

That distinction matters. If a washroom has a plumbing fault, blocked drain or failed extractor, those issues still need to be fixed. EcoBreeze is best used where the basic washroom standards are in place but odours still need continuous control throughout the day.

• Odours return quickly after cleaning.
• Washrooms have high footfall.
• Ventilation is limited or difficult to improve.
• Aerosols or plug-ins are creating an overpowering smell.
• Facilities teams need more consistent odour control.
• A fragrance-free option is preferred.
• Cleaning teams need data, monitoring or reporting across multiple washrooms.

Commercial washroom odour control checklist

Use this checklist when a washroom smells unpleasant even after cleaning.

When should you call a professional?

Some washroom odours can be solved by better cleaning and air treatment. Others need specialist help.

Do not keep adding fragrance to a washroom that may have a plumbing, damp or ventilation problem. Treat the cause first.

• The smell is like sewage, rotten egg or gas.
• The odour appears suddenly.
• Several drains smell at the same time.
• The smell returns immediately after traps are refilled.
• There are signs of leaks, damp or mould.
• Extract ventilation is not working.
• There is standing water, damaged flooring or persistent blockages.
• Staff or visitors report irritation, headaches or breathing discomfort.

What is the best long-term way to prevent washroom odours?

The best long-term strategy is a layered approach: source control first, usage-matched cleaning, plumbing maintenance, ventilation, filtration, careful fragrance and performance monitoring.

For many commercial sites, EcoBreeze can support filtration, controlled fragrance and monitoring by providing continuous carbon-based odour control and, with EcoBreeze Smart, reporting features for larger estates.

Conclusion

Persistent washroom odours are rarely solved by stronger fragrance alone. The most reliable approach is to find the source, clean the areas that are often missed, check drains and ventilation, control moisture and use ongoing odour-control technology where smells return between cleans.

For commercial washrooms, EcoBreeze can be a practical part of that strategy. It is not a replacement for good cleaning or building maintenance, but it can help facilities teams manage stale air and recurring odours more consistently, especially in high-footfall spaces where first impressions matter.