Extractor flue to flat roof

[carlvalley]

Hi Please help!! I wish to install a chimney hood to a new kitchen, i have my heart set on extracting the air outside as i've heard its much better than the filter type, my problem is, i cannot run a extractor duct pipe through the wall as i live in a terrace, is it possible to run the extractor pipe up through a flat roof? If so will i need a turn at the roof to prevent water coming down the air brick? I would be grateful if you could help.
Thanx!!

[noseall]

you can successfully vent through a flat roof no problem by fitting a mushroom vent terminal on top.

you will need a flat roof specialist to make good though.