As it is now, the exhaust duct is routed up to the attic, at floor level in the attic, the spiro pipe enters one of the chimney flues. The spiro pipe just goes straight in and ends directly (the chimney flue is sealed downwards). This means that grease and dust settle on the walls of the chimney flue, making it difficult and cumbersome to clean both the spiro pipe and the chimney flue. At first, I thought of installing an exhaust hood on the roof, but to avoid potential leakage problems in the future, I'm thinking instead of running the spiro pipe up through the chimney flue with one or two 15-degree bends to make cleaning easier. It is probably best to choose stainless steel spiro pipes/bends to make cleaning even simpler.
Is this a good solution, are there any regulations/requirements to consider?
Is this a good solution, are there any regulations/requirements to consider?
Byggnadsingenjör
· Skåne
· 1 424 posts
Exhaust ducts from kitchen fans should be fire-insulated EI15, meaning they should withstand 15 minutes of fire before spreading further in the structure. To achieve this, it's necessary to fire-insulate against combustible materials, such as at the passage through the intermediate floor with, for example, rock wool insulation. (There are ready-made, mesh-covered options for this purpose.) Regarding the cleanability of the duct, it makes sense to line the chimney with spiral ducts. An old chimney is built solely for either ventilation or smoke flues, not for the moist, grease-filled vapors from a kitchen fan. If you don't want to go out with a cap on the roof, you can lead it out through the facade, provided it does not exit directly under the eaves where moisture can cause rot or directly on the facade where it can stain the facade. It should also not be too close to air intakes for ventilation or near windows used for airing.