What You Need
- Salvaged window
- Nontreated cypress or cedar or other wood for sides
- Tape measure
- Saw and hacksaw
- 3 feet of 18-gauge perforated-steel angle
- Twenty-five 1/4-inch-diameter by 1-inch-long hex bolts and nuts
- 16 washers to fit hex bolts
- 3/4-inch No. 8 wood screws
- Three 3 1/2-inch steel or brass hinges
- Power drill and 1/4-inch bit
Step 1: Cut Wood Sides
Cut wood for sides, each 18 inches tall and matching the window's dimensions but allowing the window to overlap the cold frame by 1/2 inch.
Step 2: Attach Side Pieces
Join the side pieces, using 18-gauge perforated-steel angle. (Cut pieces with a hacksaw.) Use the 1/4-inch hex bolts to attach the angles to the wood, placing a washer between the head of each bolt and the wood.
Step 3: Attach Hinges
Attach the hinges to the underside of the window frame, using 3/4-inch-long No. 8 wood screws. Lay the window atop the box and use the hinges to mark the location for drilling 1/4-inch holes on the outside of the box. Use 1/4-inch hex bolts to fasten the hinges to the wood. Place washers between the bolts and the wood.
Step 4: Create Shelves
Stretch chicken wire across the cold frame to keep seed flats off the ground. Attach with a washer and screw.
Editor's Tip: If you anticipate your flats being heavier than the chicken wire can withstand, use lengths of treated lumber to create heavy-duty shelves.
Your cold frame will warm up quickly when the sun is shining directly on it. Always prop open the lid a little on bright sunny days, even if the air temperature is cool. On warm days, you may want to open the lid completely. Always close the lid before nightfall to preserve the day's warmth.