Dave,

I am installing a bath fan. My house is a bungalow style. I like to
vent it out by the soffit just outside the bathroom; but I am not sure
how I can get a vent pipe thru to the soffit.
My other option is to run a vent pipe down the middle of the attic
space to the side of the house vent. This pipe will have to be about 22'.

One of our bathrooms is right in the middle of our house. I did not want to
have another roof penetration, so I ran a pipe through the attic to the
side wall, about 20'. To minimize airflow restriction, I used solid 4" PVC
pipe for the straight run, with a short section of corrugated flex pipe at
the end to make the connection to the fan. It works fine and I haven't
noticed any reduction in airflow.

Anthony