Attic Ventilator

Figure A Figure B Figure C Figure D  REAL VIDEO Click here for a brief overview of power ventilator installation.

Does your attic feel like a sauna in the summer? If so, it's probably costing you a lot on your utility bill. If your attic isn't vented properly, it traps heat and warms the rest of your house. Fortunately, as Hands On hosts Walter Muellenhagen and Tony Kramer demonstrate, you can install a power ventilator to solve this problem.

Materials:

power ventilator
drill, with drill bits and driver bits
saber saw
hammer
utility knife
4" wood screw
measuring tape
caulk gun with roofing cement and silicone caulk
hammer
roofing nails
pry bar
ladder
wire stripper
wire nuts
safety glasses
work gloves
long-sleeve shirt
dust mask
shoes with good traction (for working on the roof)

Steps:

* Safety first! Make sure you have someone helping you--this isn't a one-person job. Also, make sure your ladder is secure, and wear shoes that have good traction so you don't fall off the roof.

1. First, you'll need to decide where to install the ventilator. You'll probably want it on the back of the house so that it isn't visible from the street. Also, since heat rises, you'll need to place it fairly high on the roof; however, don't put it so high up that it's visible from the street.
   
   
2. From inside your attic, measure down from the ridge beam to the height where you plan to place your fan (figure A). Mark the nearest rafter at this height.
   
   
3. Measure the span between two rafters, and mark the center point at the height where you placed your first mark.
   
   
4. Drive a 4-inch wood screw through the roof at the intersection of the two measurements. The screw should be long enough to extend through shingles; that way you can find it on the other side.
   
   
5. Make a hole in the center of the attic fan template (included with the fan). From outside, locate the screw protruding from the roof, and place the template over it (figure B).
   
   
6. Use a utility knife to score the shingles around the perimeter of the template. Be sure to press hard enough that the score lines are visible when you remove the template.
   
   
7. Remove the template and drill through the shingles inside the marked area to create a starter hole for your saber saw. Then use a saber saw to cut along the outline on the shingles (figure C). You might want an assistant to help hold up the wood you're cutting so it doesn't bind against your saw blade.
   
   
8. When the hole has been cut, you'll need to remove the shingles along the upper edge. Start by lifting the shingles and pulling the nails out with a pry bar. Try to work as gently as possible because you'll be reusing the shingles. When the nails have been removed, lift the shingles away from the roof.
   
   
9. Have an assistant help you set the ventilator in place by sliding it under the shingles above (figure D). Use roofing nails to secure the top corners. Then lift the ventilator and apply roofing cement all the way around the hole. Add additional nails all along the edge of the flashing; space the nails about three inches apart.
   
   
10. Slide the shingles you removed earlier back into place along the top of the flashing. Use a utility knife to trim off any excess shingle material next to the unit.
    
    
11. Nail the shingles back into place
    
    
12. Caulk around perimeter of flashing and over the tops of the nail heads.
    
    
13. Finally, wire the fan according to the manufacturer's instructions. You may want to hire a licensed electrician to perform this step. If you do it yourself, be sure to turn off the appropriate switch on your circuit breaker first.