Install Bath Fan Vent On Metal Roof

Draw a mark on the bathroom ceiling where you d like to install the vent fan.

Install bath fan vent on metal roof.

Use an extra long 3 8 inch diameter spade bit to bore a reference hole through the ceiling and into the attic. We explain how to install bathroom exhaust fans or vents the vent ducting the vent termination at the wall soffit or roof vent fan wiring bath vent duct insulation bath vent lengths clearances routing and we answer just about any other bathroom ventilation design or installation question you may have. Climb into the attic and clear away any insulation from around the hole. Leave the drill bit sticking through the roof so you can find the hole.

Center the nail between two rafters. Also this is the section of roof that gets hit directly with heavy winter winds. Use rigid metal ducting aluminum or galvanized steel with lengthwise seams facing up and joints sealed with foil tape or duct mastic or rigid plastic pipe. I intend to install the roof vent cap in the section to the right of the section where the plumbing vent is shown.

Secure the vent flanges with roofing nails before installing the shingles. This will involve determining the placement of the vents. From inside the attic drive a nail through the roof directly above the bathroom vent fan. Prepare the roof area.

From up on the roof use a jigsaw or reciprocating saw to cut a 4 in. If you vent through a soffit where attic vents are often located the moisture will get sucked back up into the attic or roof venting. Install the roof vent install the roof vent by sliding the top flange under the shingles above it and resting the bottom flange on the shingles below. Various size vents will come with recommendations regarding spacing and placement based on the size of the vents and the expanse of the roof.

The internal construction of the house does not permit me to vent the bathroom fan elsewhere. For optimum performance locate it between the shower and the toilet. Use a marker or a chalk line to mark the spot on the roof surface where the vent will be placed. Apply roofing adhesive on the underside of the flanges to seal.

Start in the attic and drill a hole through the roof in the desired vent location. Fwiw here is a url to the photo of the roof.