Which type of tradesman require? Bathroom extraction vent via soffit or wall

I’m curious as to how a fan has been correctly fitted yet still requires venting. If it is a recirculating version then it won’t need venting. If it is a vented model then it would have been hard to fit without a vent in place?! Anyway, to create the vent you’ll need a diamond-core 100mm drill to go through to the outside, with a section of flexible ducting to line the cavity and a grille on the outside. It is not a specialist job but you may encounter issues with needing ladders and the drill bit. That said, a straightforward job for any general builder. I would however contact the person who installed the fan and ask/check that they have installed it in accordance with the manufacturers instructions. Hope this helps.

You would need an electrician for this job. To wire up to your lighting ring

any good electrician , or if the fans are already fitted and you just need the grill fitted then a roofer or gutter person would be more than capable

It's normally electricians who deal with extractor fans but some bathroom fitters are also qualified to install these Maybe you need new rather than a vent Hope this helps

Sounds like it’s just been fitted venting into the loft which is bonkers and will fill your loft with mould and rot. Who fitted them? Get them back to finish the job properly. I bet the fan comes on when you switch the light on too which is also archaic.