On Feb 29, 7:32 am, "SteveC" wrote:
Putting in a basement appartment. I want to run 4" ducting up inside a 2x4
wall, up past the 8 foot concrete wall and outside between the floor joist.

Can I bend or squat the 4" to fit in the wall? I guess I could cut out some
of the 2" polystyrene insulation 1/2 and inch to fit.

Steve

Steve:

You must have a duct with the same cross-section area as the 4in duct.
Since a 4in duct has a cross -section of about 13 sqin, you must have
a rectangular duct of at least that cross section.

I have done what you are trying to do; installed a dryer on the second
floor and moved the vent up a wall, into the attic and to the top of
the roof. Total linear footage is about 12 feet, vertically, with only
one bend, the 90 degree between the dryer and the wall. My 4in duct
goes into a rectangular 3inx10in heating duct, and then connects at
the roof with a 4in discharge vent. I thought that I might have a
problem with the velocity of the discharge (since the area in the
rectangular duct is much larger than the area of the 4in duct), and I
have checked periodically to see whether lint accumulated at the
bottom of the rectangular duct, and none is present. That's been seven
years since I moved our laundry room to the second floor. I have had
no problem whatever. FWIW, it's a Maytag Neptune gas dryer.

Yes, I have a pan connected to a drain under the washer. Thanks.

Pierre