Odour Tracing & Smoke Testing

Persistent drainage odours are more than an inconvenience. In hospitality and commercial environments, smells can affect guest experience, staff welfare, hygiene ratings, and brand reputation. The frustrating part is that odours often come and go, and standard cleaning doesn't always fix the root cause.

ICE Drainage provides odour tracing and smoke testing across London and the Home Counties, supporting restaurants, hotels, pubs, commercial kitchens, facilities management teams, property managers, schools, and multi-tenant buildings.

We use evidence-led investigation methods to identify where odours are entering the building and why, then recommend practical remedial action to stop the problem coming back.

Why drainage odours happen

Drainage smells can come from a range of issues, including dry or failed traps in sinks, floor drains, or appliances, blocked or restricted pipework causing standing foul water, grease build-up in kitchen lines, damaged pipework such as cracks, poor joints, or displacement, ventilation issues like poor venting or negative pressure, misconnections between foul and surface water systems, defective manhole covers or poor seals, and backflow caused by a restriction further downstream.

On busy sites, symptoms are often worse at certain times, for example during peak service, after wash-down, or when the building is under negative pressure.

What is odour tracing?

Odour tracing is the process of systematically identifying where the smell is strongest, whether it's coming from internal plumbing, external drainage, or a specific run, and whether the issue is localised to one trap or area, or spread across the network.

We combine site knowledge, drainage inspection, and testing methods to build a clear picture of the source and the route it's taking.

What is smoke testing?

Smoke testing is a specialist investigation method where we introduce non-toxic smoke into the drainage system and observe where it escapes. It helps identify leaks in pipework, including hidden ones or those under floors, failed joints and cracked pipes, unsealed connections, defective venting or vent terminations, and the routes odours are using to get into internal spaces.

It's particularly useful when odours are persistent but the source isn't obvious from a visual inspection alone.

When you should consider smoke testing

Smoke testing is often the right option if odours persist after cleaning and basic checks, you suspect a hidden leak or failed joint, the smell is strongest in specific rooms such as toilets, kitchens, or plant rooms, the building has had recent refurbishments or plumbing changes, multiple tenants or units are affected, or you need evidence to justify remedial work.

It's also useful for confirming whether odours are coming from internal pipework or external drainage.

Our odour tracing and smoke testing process

We keep investigations practical, safe, and low on disruption.

1) Site review and symptom mapping

We confirm where odours are being reported, when they're worst, such as time of day, service periods, or weather conditions, and any recent changes like fit-outs, plumbing work, or drainage incidents.

2) Internal and external checks

We inspect likely contributors such as floor drains and traps, kitchen waste lines, WCs and soil stacks, external gullies and chambers, and any signs of surcharge, standing water, or build-up.

3) Targeted cleaning

If restrictions are contributing to the problem, we may recommend targeted cleaning, such as jetting, to restore flow and rule out false leads.

4) Smoke testing

Where appropriate, we introduce smoke into the system and observe escape points, such as leaks, failed joints, or unsealed connections, how well the venting is performing, and whether smoke, and therefore odour, can get into internal spaces.

5) Findings and recommendations

You'll receive clear outcomes, typically including the confirmed source and route of the odour, evidence of any defects and their likely location, recommended remedial work, and prevention recommendations to reduce the risk of it happening again.

Typical remedial actions after smoke testing

Depending on what we find, next steps might include localised pipe repairs or replacement, resealing joints and connections, trap repairs or improvements, venting upgrades or corrections, a targeted cleaning and maintenance plan, or fixing a misconnection if one was identified.

We'll always prioritise solutions that reduce disruption and stop the problem coming back.

Odour investigations for hospitality and commercial kitchens

Hospitality sites often get odours due to grease build-up and slow flow, high peak loads and wash-down routines, floor drains drying out in low-use areas, and venting issues in older buildings. We'll help you work out whether the issue is operational, down to maintenance and usage, or structural, down to defects and connectivity.

Why choose ICE Drainage?

• A commercial-first approach for hospitality and FM
• Coverage across London and the Home Counties
• Evidence-led investigations, including odour tracing, smoke testing, and CCTV where appropriate
• Practical remedial recommendations you can act on
• Credentials including Safe Contractor, SSSTS, and Constructionline Gold

ICE Drainage is a specialist service expansion of ICE Cleaning, a leading sewage cleaning company in the UK.

Book odour tracing and smoke testing

If you're dealing with persistent drainage smells, recurring odours in toilets or kitchens, or you need to pinpoint a hidden defect, ICE Drainage can help.

Contact ICE Drainage today, and we'll help you find the source and put a long-term fix in place.