A coal bunker is a convenient accessory to have around the home in the cooler months of the year. While coal is generally purchased in bags of 10 to 20 kilograms, a coal bunker will store 150 to 500 kilograms of coal and ultimately result in you having to take fewer trips out in harsh winter conditions to purchase it. If you're in the market for a coal bunker and have a knack for DIY you can make your own coal bunker at home with some basic materials from the hardware store.
Lay one of your 4-by-4-foot pieces on a flat surface. Assemble the rest of the box on top of this base.
Screw the four side pieces onto the base and onto each other.
Screw two hings to the top of the back of the box.
Screw the other wing of each hinge onto the sixth piece of wood, which will be the bunker's top.
Sand the raw edges of the box with sandpaper. Paint the box with a waterproof sealant.