- 1). Position the solar-powered attic ventilation fan on a south-facing roof (anything from southeast to southwest works), away from shading by trees or structures, for maximum sunlight exposure. Try to center the fan on the roof, between roof rafters -- do not cut a rafter to install -- and in a place to ensure maximum air movement through the attic.
- 2). Drive a nail in the center of the area chosen for the solar attic fan, leaving enough nail exposed below the head to tie string. The center of the unit should be about 2 feet below the roof ridge. Attach string to the nail. Measure 9.5" of string and attach a marking pen to the string. Holding the pen, pull the string taut from the nail and draw a 19" circle onto the roof shingles.
- 3). Cut the diameter of the hole using the reciprocating saw.
Caution: Do not cut through the roof rafters or weight-bearing structure!
If a roof rafter runs through the cut hole, leave the rafter in place. Remove ONLY roof sheathing. - 4). Use the utility knife to cut a 4-inch slit through the shingles and tar paper at the three and nine o'clock positions on the hole (six o'clock being on the downslope), allowing for the fan flashing to be inserted under the shingles.
- 5). Insert the reciprocating saw sideways under the shingles and cut all nails from the 3 o'clock position up and around to the 9 o'clock position on the hole. Take care not to damage the remaining roof shingles. This removes nails that will keep the fan flashing from sliding up underneath the shingles.
- 6). Caulk underside of flashing with caulking material. Two concentric rings of caulking material suffices.
Note: Installation on a tile roof requires a skirt. - 7). Slide flashing under tar paper and shingles, pushing flashing up until the shingles butt against the raised portion of the flashing, without smearing caulk on exposed shingles. The bottom side of the flashing will rest on top of the shingles. Fasten flashing with four Phillips-head screws at the 3 o'clock, 6 o'clock, 9 o'clock and 12 o'clock positions. The 3 o'clock and 9 o'clock position screws go under the shingles. The 6 o'clock and 12 o'clock position screws go on top of the shingles.
- 8). Caulk over the screw heads at the 6 o'clock and 12 o'clock positions, as these will be exposed to the weather. Also caulk the areas where the 4-inch slits were made and around the top 180 degree portion of the fan housing where shingles butt up against the raised area of the flashing.
- 9). Attach the adjustable brackets to the side of the solar panel frame. Be careful -- solar cells are fragile. Adjust the solar panel in a position to expose it to the most sunlight possible throughout the day.