Great forum!!!
Not sure if this is the right place for this question, but...

During re-model of house, went into the attic to check status of dryer vent duct. Laundry area is in middle of houe (concrete slab) so dryer is vented thru 4" duct between back wall, straight up thru attic space to roof vent. Lo and behold, the idiots who built the house never extended the duct to reach the roof vent !!!!! Lint every where !!!!

So, my question is, after I connect the duct to the vent, I have seen advice that says that the dryer duct that passes thru unheated attic space should be insulated to prevent condensation. I bought some 1/2" aluminum-foil covered fiberglass wrap to wrap around the duct, but (this may seem like a dumb questions), do I wrap the insulation around the duct with the aluminum side out or the aluminum side against the duct?