Forced air ducting question

[Petar]

I am planning to fit the ducting in my boat before buying the diesel forced air heater. I know where I want it and how to fit it. The question i have is, if the Home Depot flexible ducting (which seem to be for clothes drier exhaust only) is adequate from temperature aspect? The guy at Home depot told me only 26 gauge rigid sheet metal ducting is to be used for the forced air heat ducting and not the flexible ones??? Is that the fact? Do I need to go and buy the ducting from heater company which charges $6 / ft?

[MBWhite]

The definitive answer is to do what the installation manual for the heater you buy says to do. You should go for rigid ducting whenever possible because it will flow noticeably more air that the cheap flexible stuff does but the actual answer to your question is to install it according to the manufacturers requirements.