Install Bath Fan Vent On Metal Roof

Leave the drill bit sticking through the roof so you can find the hole.

Install bath fan vent on metal roof.

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. The internal construction of the house does not permit me to vent the bathroom fan elsewhere. Draw a mark on the bathroom ceiling where you d like to install the vent fan. I intend to install the roof vent cap in the section to the right of the section where the plumbing vent is shown.

Also this is the section of roof that gets hit directly with heavy winter winds. 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. In this video this old house general contractor tom silva shows how to properly install a roof mounted bath fan vent. Prepare the roof area.

This will involve determining the placement of the vents. From up on the roof use a jigsaw or reciprocating saw to cut a 4 in. From inside the attic drive a nail through the roof directly above the bathroom vent fan. Climb into the attic and clear away any insulation from around the hole.

Various size vents will come with recommendations regarding spacing and placement based on the size of the vents and the expanse of the roof. Secure the vent flanges with roofing nails before installing the shingles. Use an extra long 3 8 inch diameter spade bit to bore a reference hole through the ceiling and into the attic. For optimum performance locate it between the shower and the toilet.

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. 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. 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.

Center the nail between two rafters. Start in the attic and drill a hole through the roof in the desired vent location.