Start in the attic and drill a hole through the roof in the desired vent location.
Install bathroom exhaust fan roof.
For optimum performance locate it between the shower and the toilet.
The installation is easiest if you re replacing an existing fan.
A single exhaust exits through the roof figure a.
You can use the existing switch wires and ductwork.
Try to keep it close to the fan location.
This setup requires an in line centrifugal fan mounted in the attic drawing air simultaneously from both bathrooms see photo.
Draw a mark on the bathroom ceiling where you d like to install the vent fan.
Place the fan in the cut out hole so that the bottom edge of the fan is flush with the bottom of the ceiling drywall.
A grille in each bathroom attaches to ducts which then fasten to a y connector at the fan.
Access the attic and bring your light cordless drill screws and bathroom fan housing.
Climb into the attic and clear away any insulation from around the hole.
You will need a partner for this step as you cannot see the ceiling from this position.
Leave the drill bit sticking through the roof so you can find the hole.
Use an extra long 3 8 inch diameter spade bit to bore a reference hole through the ceiling and into the attic.
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.
This system is quiet too.
You mount a switch in each bathroom.
Apply roofing adhesive on the underside of the flanges to seal.
Sinnisjinsulator video includes how to and tips on attic bathroom fans and proper placement and insulation of exhaust hose.
Use the information below to select a fan.
Also it helps to get a fan that s the same size as your existing fan so you won t have to adjust the size of the ceiling hole.
From up on the roof use a jigsaw or reciprocating saw to cut a 4 in.
Most roof overhangs today have continuous soffit ventilation strips.
Secure the vent flanges with roofing nails before installing the shingles.