We cut the supports 16 in. long, but you can place the second shelf at whatever height you like. Screw the end supports to the walls at each end. Use drywall anchors if you can’t hit a stud. Then mark the position of the middle supports onto the top and bottom shelves with a square and drill 5/32-in. clearance holes through the shelves. Drive 1-5/8-in. screws through the shelf into the supports. You can apply this same concept to garage storage. See how to build double-decker garage storage shelves here.
Aside from the privacy it offers, a latticework porch trellis is a perfect way to add major curb appeal to your home for $100 or less. The trellis shown here is made of cedar, but any decay-resistant wood like redwood, cypress or treated pine would also be a good option. Constructed with lap joints for a flat surface and an oval cutout for elegance, it’s a far upgrade from traditional premade garden lattice. As long as you have experience working a router, this project’s complexity lies mostly in the time it takes to cut and assemble. Get the instructions complete with detailed illustrations here.