Old extractor fan vent size adapter

[boxtree]

Hi Guys,

I've moved into a property (1985 build) which has a bathroom vent above the shower.
As you can see from the pics the vent is just covered in loft insulation which has gone a bit, errrr, bad.

I'm going to fit some ducting. However everything current seems to be 100 or 120mm. The round vent hole seems to be around 94mm.
Does anyone know which adapter/convertor I can use to link the existing hole up to a standard 100mm duct/fan.

Cheers

 

[JohnD]

The thing you have photographed is an adaptor plate.

Measure the duct itself.

 

[Taylortwocities]

There are size adapters, should you need one, like this

https://www.amazon.co.uk/Universal-ventilation-diameter-connector-transition/dp/B075T85JV8/ref=asc_df_B075T85JV8/?tag=googshopuk-21&linkCode=df0&hvadid=256152831496&hvpos=&hvnetw=g&hvrand=17298630606224388779&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006789&hvtargid=pla-420183524056&psc=1