DIY Concrete Curbing Molds

Measure across the top of the gutter. Typical gutters are 5 inches, 6 inches or 7 inches across the top. Cut two pieces of 1-inch by 6-inch wood the width of the top of the gutter. Add 2 inches to your measurement. Your board will be 1-inch by 6-inches by 7-inches, 8-inches or 9- inches. These are your end pieces.

Build a rectangle. Attach one of the end pieces to the end of one of the long pieces with two screws, so you form an L-shape. Then, attach the other long piece to the other side of the end piece to form a U-shape. Attach the end pieces to the outside of the side boards. Then, attach the final end board to the outside of the other ends of the side boards. You should have a rectangle support now.

Place the rectangle support on a flat surface and slide the 10-foot plastic inside it. It should fit snugly inside the rectangle. Place it close to where you will be installing the curb, because it is very heavy.

Hammer wood stakes along the outside of the wood rectangle support every 18 inches to 2 feet. This will keep the wood and gutter in place so it will not bow out when you pour the concrete into the gutter. Stake both of the long sides of the support. Screw the stakes into the support sides.

Paint the vegetable oil onto the inside of the gutter and the wooden end pieces so that everywhere the concrete will be poured is covered with vegetable oil.

Mix your concrete and pour or shovel it into the gutter. Cover the concrete with plastic sheeting and let it sit for two to three days.

Remove the curb from your form. Remove the stakes from your form support and disassemble your support so the gutter is free. Roll the gutter over and dump the curb out of it. Bend the plastic out a bit to encourage the cement to fall out. Spray the curb each day for seven days and cover it with plastic. Do not move the curb for at least a week.