There is a window on the wall behind the dryer but the window is just below ground level. The window leads out to a window well on my patio which is covered by a steel grate.
One option which I really don't want to do is to take out one of the two side-by-side pieces of window glass and replace it with plexyglass with a cut out for the 4" round dryer vent. This would route the hot air out into the window well but, over time, all of the dryer lint would coat the inside bricks of the window well. Probably the outside of the remaining window glass too. There'd be no good way to clean it if that happened.
Most all drier vent tubes are flexible aluminum or plastic in a 4" diameter. There is a possibility that if I didn't have to use the 4" venting pipe/tube I'd be able to drill a small hole in the wood header near the window. But even if I did, the vent would be just above the patio slate.
There's got to be a way to vent my dryer to the outside, but my basement is entirely below ground and there's no path to get outside other than through the top of the header. Are there smaller diameter hoses that I could use to dead-end into a smaller vent cover that could be mounted outside? Any, and I mean ANY, suggestions are most appreciated.