Laundry vents in a cold climate
OK, from the sublime to the ridiculous, unless you consider not wasting heating oil sublime:
The vent to my dryer used to vent directly into a crawlspace under the house. This was bad, because it wasn't up to code, because the moist air led to mildew, and because -- believe it or not -- the crawlspace had been insulated with straw, so the arrangement had only avoided a fire by some sort of special dispensation.
So, now the dryer is vented out through the wall of the house. However:
Cold air still gets a straight shot into the house through the louver, the hose, and the driver. (Technically, the new arrangement is an improvement, since at least now I have a louvered vent, as opposed to the old arrangement, where the hose from the dryer opened directly onto the crawlspace, which, in the winter, might as well be the outside.) Plus, I notice that the corrogated hose that leads from the wall to the dryer is cold.
So, is there any way to cut down on the heat loss from the dryer vent?
I could "louver the louver," but it seems that giving the dryer exhaust a straight shot to the outside is necessary to prevent a lint fire.
I could wrap the hose in pink insulation stuff, but it seems that the real issue isn't cold coming off the hose, but cold air coming through it.
Anyone with experience have any thoughts on this?