There's A Bathroom Vent Around Here Somewhere

In an attic I found one bathroom exhaust vent, but not the other one, and I thought, "There's a bathroom vent around here somewhere."

The problem with the one I could see is that it has been venting into the attic space for so long the moisture has damaged the roof sheathing.

Judging from the amount of damage, this may have been the case with the previous vent.

Bathroom exhaust fans should vent the air (and humidity) directly to the outdoors.

So, if this one is venting indoors, what about the other one?

I looked.  As much of the attic floor had been covered with plywood (crushing the insulation everywhere it lay) I could not see the metal box anywhere.

Calling down, I asked the agent to turn on the fan.

And I could hear it!  But I could not see it.

Crawling around with my ear to the plywood I found it.

At least as near as I could tell.

There it is!

Can you see it?

Neither could I.  But that red circle is very close to where it is.

Can you imagine what a mess it is under that plywood?

As an aside, to be effective insulation needs to be fluffy, puffy and deep.  Insulation derives its R-value (insulation ability) from its depth.  And that is true no matter the insulating product - fiberglass, cellulose or foam.

Crushing it with plywood, or storage of any sort, reduces its insulating ability virtually to zero. 

Insulation traps air to provide a thermal barrier.  Compacting any insulation traps less and less air, which, in turn, reduces its insulation ability.  Therefore heat will transfer through it more easily, in or out.

But plywood that blocks a bathroom vent is worse still!  That will prevent the heat from the fan motor from dissipating, and unit can overheat!  Plus the air it blows, and humidity, go no where.

My recommendation:  if you see your home inspector crawling around on plywood in the attic with his ear on the floor, he is probably doing it for a reason!  See what he comes up with!  When all is said and done it might be an important find!