Dryer Venting down and under floor.

[gwelte]

I have a dryer that is located on an inside wall that I want to vent by going down and under the floor 180 degrees out to the opesit wall that is an outside wall. The pipe run would be about 9 feet.
The run would be a 90 degree out of the dryer, 14 - 18 inchdown through the floor, another 90 deg. turn, then a 9 foot run out through the exterer wall.

Is this OK or will there be an air flow issue. I plan on using 4 inch galv. pipe.

[Jay11J]

Your fine with what you are planning on doing.. Seal the joints with foil tape.. Don't use sheet metal screws.

The outside vent hood should have an opening of 4" or use the vent hood that has about 3-4 1" flapper.. Older vent hood opens about 2".

[Ed Imeduc]

Be sure and support that 9ft run from the joist there with wire are bands to hold it up.

ED ;)