Reducing extractor pipe diameter for last section?

[jonshutt2]

Hello

Just looking for advice. I've just replaced a pretty old kitchen extractor hood, all good, but I've noticed the old one has a 10cm diameter pipe, the new one fits 150cm pipe. The total length is about 3m.

The problem I have is the old pipe pushes through a gap about 10cm between the roof and the top of the external wall, and down the gap and out through a 10cm hole in the soffit.

Options I've thought of - but happy to have opinions...

- leave the last 30cm of old 10cm hose, and fit new 150cm between the hood and the last bit
- squash a 150cm hose down so the last 30cm or so is 10cm high
- get a roofer to come fit a vent through the roof which I can connect the pipe to

thanks

 

[Murdochcat]

Use a reducer on between your new extractor and the existing vent pipe