6. Pallet Wood Butterfly Tower
Pallet wood is free, weathered, and already has the rough texture butterflies like. This tower design stacks three or four small chambers vertically, which gives you several microclimates in one shelter.
Materials: pallet slats, a circular saw or handsaw, exterior screws, wood glue, sandpaper, and a pry bar for disassembly. Always check pallet stamps and avoid wood marked MB, which indicates chemical fumigation.
Cut slats to build a tall, narrow box roughly 8 inches wide, 16 inches tall, and 4 inches deep. Add two horizontal dividers inside, each with a gap at alternating ends so the chambers connect. Cut a vertical entry slot in the front of the bottom chamber and a second slot in the middle chamber.
Time: 2 hours. Difficulty: intermediate. Mount it on a fence post or shed wall. Because it has multiple chambers, it can shelter several butterflies at once during a cold snap.