I saw an article in a magazine with instructions of building a rain barrel. I have wanted them since last season, thinking of the saving for watering the gardens.
The article advised to use a 55 gal. trash can (Plastic) to make the barrel. Don't use them! They are not strong enough! I found 55 gal barrels for $ 12.00 each including the gas to get them. I made two a couple weeks ago. Since we've had a nice rain, I've made some changes to make them even better!
The article advised making an overflow hole near the top with a 1/2 " outlet. My barrel collecting water from the top back roof filled up quickly and the 1/2 " overflow will not handle the water from a 2 X 3 gutter.
Today I removed the 1/2 " overflow outlet, cut a hole large enough to run a gutter out. I silliconed the gutter where it exited the barrel.
I attached a flexible piece coming off the house gutter, angling it towards the barrel, a straight piece, long enough to reach the barrel, and an angled piece directing it over my screened inlet area. The spiket was too high on one barrel, leaving too much water remaining in the barrel, so I bore another hole, much lower in the barrel side. Instead of securing the bib valve with a nut inside, I used a # 14 O Ring and siliconed the threads good. I plugged the original hole, using my 1/2 " Overflow outlet and filled it with silicone.
Here's how to build it and what I used:
A 55 Gal barrel, suitable for holding liquids. Cut a hole in the top for your downspout, and screen to cover it. I used tin snips to cut some flashing into strips. I spread a bead of silicone around the edges of the screen, laid it over the hole, layed my flashing strips around the outer edges, drilled small holes through the flashing and screen, and secured it down with small sheet metal screws. Rivets would work fine, too.
Next, I cut a hole in the side near the top, to accommodate my overflow gutter. I inserted an angled gutter spout in the hole and siliconed a seal around the seam. I then configured the rest of the gutter pieces to move the overflow water away from the foundation. Using a spade bit, 3/4 " size, drill a hole near the bottom of the barrel for your faucet. I used a 1/2 " boiler valve, a # 14 O Ring over the threads, a bead of silicone, and simply screwed the valve slowly into the hole, making sure to keep the valve aligned straight. The barrels sit on two layers of cinder blocks and a couple 2 X 4 's
That's about the size of it!