What tradesmen have diamond core drills?

Most kitchen fitters keep core drills as part of their kit,because of fitting extractor hoods. Some electricians carry core drills because they generally fit the extractor fans. So if your having a fan fitted like an Expelair I would post for an electrician,but if your having a cooker hood fitted over a hob you want a kitchen fitter.

Any professional kitchen fitter would have the experience and the tools for this job. It is not just drilling hole, where it should exactly be also comes with experience.

160mm seems rather large for an extractor fan duct, the extractor fans that I fit use 4inch ducting and I use a 117mm core bit on them. So to answer the question, I'm an electrician and have a core set but not one that large. Electricians are normally the ones that wire up the fans, so would suggest you point the job towards them. Plumbers are another trade that hold cores for drilling out flue and waste pipes. Failing that, general builders are likely to have them too. Andy The

Electrician

I fit kitchens and I have time and Corbits but only up to 5 inches if you want 150 or 160 mil hole but 6 inches and above so a normal extractor hole would be four or 5 inches and I have the drillbits for those

A good kitchen installer will have one also a bathroom installer/plumber and a local builder can hire one if he doesn’t have one

Standard sizing for extractor ducting would be 100mm. Most kitchen fitters, bathroom fitters or general builders will have a diamond core set on board.