Multi-tenant buildings: shared duct responsibility

It must be clearly allocated - commonly the landlord (as the shared-system owner, often via service charge), or shared among the tenants - depending on the leases; it isn't automatic, so establish it from the leases. Where several kitchens share one extraction duct, responsibility for cleaning that shared duct must be clearly allocated. There's no automatic rule, but common patterns are: the landlord (as the party responsible for the shared, building-wide system - often cleaning it and recovering the cost via service charge); or the tenants collectively; or as the leases otherwise provide. The individual tenants are usually responsible for their own kitchen's extraction (canopy, filters, ducting within their unit), but the shared duct is the specific question. So who cleans it depends on the leases and building arrangements - which must be established (with legal advice), so there's a clear owner rather than dangerous ambiguity. So it depends on the leases - commonly the landlord, but establish it. So the leases decide - often the landlord. This is general commentary, not legal advice.

Because it accumulates the combined grease of all the connected kitchens, and a fire in it could spread through the building and affect all the tenants - not just the one whose cooking started it. A shared duct carries the grease-laden air of all the kitchens connected to it, so it accumulates grease from all of them - everyone's grease building up in one duct (potentially a lot, being several kitchens' worth). And that grease is a fire risk (fuel), so a fire in the shared duct, fed by the combined grease, could take hold and spread through the building - endangering all the tenants, not just one. So the fire risk is collective: a neglected shared duct endangers everyone in the building, and each tenant's grease contributes to a risk that could harm all of them. This makes keeping the shared duct clean a matter of collective fire safety - protecting all the tenants. So it's a shared fire risk because everyone's grease is in it and a fire affects everyone. So because everyone's grease fuels a shared fire. This is general commentary.

It goes uncleaned - each party assuming another does it - so the combined grease builds up and a shared fire risk develops unmanaged, endangering everyone, until a fire or inspection exposes it. With a shared duct, responsibility is diffuse (several tenants and the landlord), so if it isn't clearly allocated, the assumption gap is severe: each tenant may assume the landlord or the other tenants clean it, and the landlord may assume the tenants do - so nobody actually cleans the shared duct. The result is that it goes uncleaned, the combined grease of all the units builds up, and a shared fire risk develops unmanaged - endangering everyone in the building. Because the risk is collective but the responsibility diffuse, this can go unnoticed until exposed by a fire, an inspection, or a fire risk assessment (and then a dispute over who was responsible). So the shared duct falling through the gap is a real and dangerous outcome - which clear allocation prevents. So it falls through the gaps and a shared fire risk builds. So it goes uncleaned and dangerous. This is general commentary.

Usually you're responsible for your own kitchen's extraction (canopy, filters, ducting within your unit); the shared duct beyond depends on the leases - often the landlord's - so check, and don't assume the shared part is covered. In a multi-tenant building with a shared duct, the typical division is that each tenant is responsible for their own kitchen's extraction - their canopy, filters, and the ducting within their unit up to where it joins the shared duct - while the shared duct beyond (serving all the units) is separately allocated, commonly to the landlord or shared among the tenants, per the leases. So you're usually responsible for your own part, but the shared duct is a separate question that depends on the arrangements. The key is not to assume the shared part is someone else's job and therefore covered - establish who is responsible for the shared duct, because if no one is clearly, it may be going uncleaned (a risk to you too). So check the leases for the shared-duct responsibility. So your part is yours; the shared duct depends on the leases. This is general commentary, not legal advice.

Pin down who is responsible (from the leases, with advice), ensure they arrange it - to TR19 Grease, at a frequency matched to the combined cooking, with records - and coordinate it with the tenants' own extraction cleaning. To ensure a shared duct is cleaned, first establish clear responsibility for it (from the leases and building arrangements, with legal advice) - so there's a definite owner (the landlord, the tenants collectively, or as agreed), not ambiguity. Then ensure whoever is responsible arranges the cleaning: the shared duct cleaned to TR19 Grease, at a frequency matched to the combined cooking of all the connected units (which may load it fast, being several kitchens' worth), with records. And coordinate it with the individual tenants' own extraction cleaning, so the whole system (each kitchen's part and the shared duct) is properly covered. All the tenants have an interest in this being done (the risk is collective). So make sure it's cleaned by pinning down responsibility and coordinating the cleaning. So establish the owner and coordinate the clean. This is general commentary, not legal advice.

Its frequency should be matched to the combined cooking of all the connected units - several kitchens' worth of grease can load it faster than a single kitchen's duct, so it may need frequent cleaning. The right cleaning frequency for the shared duct is set by how fast it accumulates grease - which depends on the combined cooking of all the kitchens connected to it. Since it carries several units' grease-laden air, it can accumulate grease faster than a single kitchen's duct would (the more, busier, or greasier the connected kitchens, the faster). So the shared duct may need frequent cleaning, matched to the combined load - not assumed to be the same as a single kitchen. The frequency should be set on a risk-based assessment of the combined cooking. So yes - with several kitchens on it, the shared duct may load faster and need frequent cleaning, matched to the combined cooking. So its frequency reflects all the connected kitchens' cooking. So matched to the combined load. This is general commentary; the frequency should be risk-based.