Don't let a code authority or an insurance man know what you are
doing. That run of duct will need to be welded steel with fire
suppression. No joints allowed. It should technically be a
grease hood with Halon, but they may reluctantly allow adapting a
conventional hood with a remote Ansul valve. As far as I know,
you will need to install an exterior grease fan, not a push type.

Ain't code compliance wonderful?

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______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)




"Mike Hartigan" wrote in message
.net...
I'm finishing up my basement bar that includes a range with a
grill.
These beasts tend to generate some smoke, so a vented exhaust is
a
must. I've got a nice, beefy blower, but I'm concerned that the
20'
duct that will be installed above the suspended ceiling will
leak
smoke and/or grease, particularly since the blower will be
installed
at the hood, meaning that there will be positive pressure along
the
entire length of the duct. How can I minimize this? 4" PVC
would be
nice, but I suspect that it wouldn't be well suited to this
application (and probably not code). What are my options?