Going to the soffet is 12 feet.
Venting bathroom fan through roof.
Leave the drill bit sticking through the roof so you can find the hole.
This involves running ductwork from the fan usually though an attic and out through the roof.
Options for venting a bathroom exhaust fan include best to worst.
Behind a soffit vent.
Start in the attic and drill a hole through the roof in the desired vent location.
Try to keep it close to the fan location.
Behind a gable vent.
In order to accomplish this the roof has to have a hole cut in it.
From the roof find the nail and use the utility knife to cut roof shingles from around the nail.
From inside the attic drive a nail through the roof directly above the bathroom vent fan.
No need for special tool.
In this video this old house general contractor tom silva shows how to properly install a roof mounted bath fan vent.
Choice is go up to roof 5 6 feet or out the present vent 15 18 feet with insulated pipe or shorten the line by going straight to side of home but this requires going up high with latter to drill a new vent hole as tight quarters in attic prevent drilling from attic.
Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof.
Through the roof or an exterior gable wall.
Robert s has the largest base flange of any bath roof vent cap which makes it super easy to install and make watertight on the roof.
It is because of this that many builders tend to advise against this method.
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