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PART F VENTILATION TESTING

Kitchen Extractor FanThis is required for new builds to pass Part F of the building regulations in England. It is often also required by the build insurance company.This prevents the build up of moisture that would otherwise cause mould and damp and maintains a sanitary conditions.

Onsite vent testing measures the actual volume of air the extractor fans pull, normally specified in litres per second (l/s). The testing is non-destructive and usually takes up to 1 hour to complete for a single dwelling with the results being confirmed immediately onsite and the certificates can be issued on the same day.We charge less if the extractor fan testing can be done during the same visit as an airtightness test.

Extraction is required in Kitchens, utility rooms, and any rooms with baths showers sinks or toilets. If you install individual intermittent fans that are turned on or off as required by a switch or activated using the light switch circuit, these are known as Type 1.

To convert from cubic metres per hour to litres per second:divide by 3.6.

Here is a quick guide to how to get your dwelling to pass

How to achieve success with the Part F Extractor fan test

Know what flow rate is required for the room. Kitchens require 30 l/s if the extractor is above the hob, or 60 l/s otherwise. Rooms with a bath or shower require 15 l/s. Sanitary rooms with just a toilet or handwash basin require 6 l/s. Utility rooms require 30 l /s (normally a six-inch fan).

Fans are often specified with flow rates for ideal lab. conditions without any terminals or ducts attached. Flow rates drop off quickly because ducts terminals kinks and bends. Often the final rate will be less than half that rated on the box so bear that in mind when ordering the fans.The lengths of ducting should be kept as short and as smooth inside as possible e with minimum bends - flexi-duct is not good as the ridges, bends and kinking significantly reduce flow. Pay attention to the terminals at both ends - flaps that prevent back-draught also reduce flow. Roof terminals can also be restrictive.

Here is a list of things to check when you order a test from us…

  • No fan present - where required (cooking, bath, shower, toilet, utility)
  • A recirculating kitchen fan (fails because does not extract moisture to outside)
  • Fan not working (no electricity)
  • Blocked pipework (debris, kinks or flexi-duct that is too long or compressed behind terminals)
  • Multi speed fan set to wrong speed

If you have a loft or void space, then install an inline fan as this usually performs much better. Check that multi speed fans have been set to the correct rating - two speed fans frequently have a jumper inside their electrics. Please check that the fan is installed, wired up and working before the test.

Now you are ready to test…. Give us a call.

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