Our bathroom has a ceiling light fixture whice I would like to replace with an exhaust fan. I understand the need to vent this out of the attic and to have the duct well insulated to avoid condensation. The problem is access to the outside. We have a roof with four sloping sides, no vertical ends. The house is covered with vinyl siding including the soffitts. The side of the house where the bathroom is located is three stories above the ground. Yours truly does not "do" heights.
Do I have any reasonable options to vent a ceiling bathroom fan? I have heard it is good to keep holes in the roof to a minimum to avoid leaks. Thanks in advance.
Paul McC

Thou I cannot quote the exact code, venting restroom fumes and moisture from one space into another is not allowed.

Any moisture introduced into the attic can condense and cause the insulation to get wet, which will not dry out quickly, and possibly cause damage to the finishes below, reduce the ability to insulate, and cause mold to grow.

Any attic should have venting to allow the space to "breathe", attic spaces are normally and should be the same temperature as outdoors, to prevent even moisture in the air from accumulating and causing damage. I think this is what you mean by "holes in the roof"

If there is venting slots in the overhang, perhaps running the duct up to and near this opening will help, if installing a direct vent to outdoors is difficult. Otherwise, you may need to wait until someone gets on the roof to install a vent cap through the roof to attach the duct to.

I hope this helps.

TKRussell-
Thanks for the response. I am aware it is not proper and not smart to directly vent warm, moist bathroom air into a closed attic space. My dilemma directing a vent out of the attic is having an attic with no vertical sides. The options seem to be a roof stack with the risk of that leaking rainwater into the attic, or perhaps directing a horizontal duct from the fan to a nearby soffitt. The issue there is how to make the opening in the soffitt from the attic and how to close that to avoid critters (birds squirrels,etc) from nesting in the duct connected to the soffitt, without having to climb three stories to access the soffitt from the exterior. It would seem pretty straightforward if yours truly was not adverse to being three stories up on a ladder!
Thanks for your time and thoughtfulness.
Paul McC

I had to install a bathroom fan vent through a vinyl-sided wall three stories up and did it from the inside as follows.

- Cut hole through the wall from the inside using a sawzall.
- Attach the plastic duct cover screen/louvre on to the short piece of duct that is sold with it. Use lots of caulk and small screws through the side.
- When the caulk above is dried, attach a loop of string to the covering that extends into the duct and attach to a cord that runs into the attic.
- Put a LOT of caulk around the part of the assembly that will touch the house.
- Pull the duct assembly to the hole in the wall from the inside using the cord.
- When the duct assembly is near the hole, reach through with your hand and pull it tight against the house and hold it for a while.
- Apply caulk to the inside of the duct-wall connection.

It might sound strange, but it has worked for me!

dclynch-
Sounds brilliiant. This just might be my solution! Thanks for your time and wisdom.
Paul McC