How to Make Your Own Rain Barrel

make your own rain barrel

Rain rain everywhere and now I can capture it in my rain barrel!  With only 500 sqft roof surface, it takes less than 0.25″ of rain to fill up a 55 gallon drum.  Why waste that water when you can use it to water plants, flowers,  grass, and even washing your car!

Just thinking about constructing a rain barrel was a little daunting but as it turned out, it was actually quite easy.  The most difficult part was finding a 55 gallon plastic barrel that not only conspicuously blended in with the house and shrubs but also could be procured at a reasonable price.  After a few calls, I ended finding a warehouse distribution company that sold used (and clean) barrels for a third of the price you typically see online vendors.  Once I had the barrels, the next step was to figure out how to actually configure them.  I looked all over the internet and wasn’t very motivated by my results.  Some methods were quite pricey and some methods we not just feasibly possible with the aesthetics I was going for.  My husband got involved and we spent some time at a hardware store piecing the puzzle together while trying to keep things as simple as possible.

We have put this barrel into service through 5 significant rain events lately and it has passed with flying colors.  The only thing that surprised us is how quickly the barrels fill up!

This is what we came up with…..


  1. 55 gallon clean plastic drum with a removeable lid.
  2. 3/4″ threaded hose bib
  3. 3/4″ threaded female copper joint 
  4. silicone sealant
  5. screen material to filter debris out of the water and keep mosquitoes out.
  6. 2 gutter elbows (take a look at your downspout configuration, there are a lot of ways to do this)
  7. pavers, gravel, or another option to use as a base to stabilize and elevate your rain barrel.


  1. Drill
  2. 1″ inch flat bitIMG_1084
  3. 3/8″ drill bit (optional based on lid type)
  4. Hacksaw (if needed to cut gutter)
  5. Jigsaw with blade to cut plastic


1.  Prep the barrel.  We were fortunate enough to track down black barrels.  I’ve seen bright blue and that is a color that would not work for me!  If you don’t like the color, buy some spray paint at the local hardware store and go to town!  We had one gray ring for the lid to spray paint black.  Once we did that we were all set!

2.  Scope out locations.  Take a look at your gutter downspouts and roof area around your house and determine the best place to put a rain barrel.  We have a side of our house that seems to not drain as well as others.  Putting a rain barrel there eliminates at least a small portion of the water coming from the roof and draining to that area. This spot is also conveniently camouflaged by some bushes. Done!

3.  Prep your base.  The base that your rain barrel will sit on needs to be stable and slightly elevate the rain barrel off the ground.  Elevating the rain barrel makes it more convenient for you when you want to access the hose bib for a hose, pail, or watering can and it also increases the hydraulic head height.   To prep out base we placed three pavers in the area we were planning to install the barrel and leveled them.  Make sure the base is stable because a full 55 gallon drum will weigh over 450 lbs. 


4.  Drill the overflow hole.  In case your rain barrel fills up completely due to heavy rainfall (not hard to do), you need to have a way for the barrel to overflow.  This hole should be drilled on the side of the barrel a few inches from the top.  Use your drill and a 1 inch flat bit.  This is great practice to test the size needed for the hose bib which comes up next.   One lesson learned is that even though is a simple overflow, the position on the barrel can be quite critical, you want it to overflow on a side of the barrel that will not promote erosion or lead to water against your house foundation.


 5.  Drill the hole for the hose bib.  Use the drill and the 1 inch flat bit to make the hole for the hose bib.  It may be helpful to put the rain barrel in place and consider how you will be using the hose bib and access needed.  For this rain barrel we intend to install a soaker hose for watering the beds nearby.  The other rain barrel will be to water our container gardens.  You want to place it at least about 4 inches from the base to allow for easy access.  Once the hole is drilled you can screw the 3/4″ threaded hose bib into the hole and apply silicone sealant on the threads as needed.  At this point it would be helpful to have a second pair of hands since you will need to lay inside the barrel to hold the 3/4″ threaded female joint the hose bib while tightening


6.  Cut the downspout.  Place the rain barrel in position and determine where you should cut the downspout.  Remember, “measure twice, cut once”.  Put the elbow pieces together and determine how you are going to make the transition from the downspout to the barrel hole.  Your barrel may have a different lid that ours did.  We decided to cut a hole in the middle of the lid and position the downspout elbows to terminate at the hole in the middle of the lid.  We found it helpful to figure out how this part was going to work for us BEFORE we started cutting holes in the lid.  We marked the downspout for where we needed to cut.  Reuse the existing bottom downspout up to a new location to hold the downspout in position.


7.  Install the elbows on the downspout.


8.  Cut the hole in the lid.  Place the rain barrel in position under the elbows and draw on the lid the area that should be cut for the hole. We also drilled a few 3/8″ holes in the lid in low spots to minimize standing water on the lid.



9.  Install the screen.  Remove the lid.  Cut a small piece of screen material use the Gorilla Glue (or similar) adhesive to secure it over the overflow hole.  This keep mosquitoes and debris out of your water.  You will be amazed at how much debris comes off of your room during each rain event.  Cover the top of the rain barrel with the screen material.  Put the lid back on.  The screen material should be secure once the lid is on and you can trim around the edges of the lid to remove the excess screen material.


10.   Install the rain barrel.  Congratulations!  Now do a rain dance and test out your new rain barrel!

DIY rain barrel

Post Rain Event Lessons Learned 

1. It doesn’t take much rain to fill the barrel.  If you can estimate your roof area draining into the barrel, use the equation below to determine how much rain will it take

Sample Calculation

Rain barrel volume can be determined by calculating the roof top water yield for any given rainfall, using the following general equation: 1
Equation 1.    V = A2 x R x 0.90 x 7.5 gals./  ft.3        where:
V = volume of rain barrel (gallons)
A2 = surface area roof (square feet)
R = rainfall (feet)
0.90 = losses to system (no units)
7.5 = conversion factor (gallons per cubic foot)

Example: one 60-gallon barrel would provide runoff storage from a rooftop area of approximately 215 square feet for a 0.5 inch (0.042 ft.) of rainfall.   

60 gallons = 215 ft.2 x 0.042 ft. x 0.90 x 7.5 gallons/ft.3

Source: Urban Design Development – Low Impact Design

2. Strategically place your overflow.  Placing it on the wrong side of the barrel can lead to water collecting along your foundation.

3.  It may be easier (and less traumatic) to just buy a new section of downspout rather than cutting your existing.  Just remove the existing and store away in case you ever move your rain barrel or don’t like it.

4.  There are many different downspout clips that may work better.  After we built the barrel, we found a downspout clip that keeps the downspout in position vertically on the wall but allows it to be pulled out from the wall.  This kind of setup allows for better access when taking off the lid.

5.  In light rains, the rain water will adhere to the downspout so the back of the the downspout needs to be fully over the lid hole so that it drains into the barrel properly.

6. If the rain barrel will be placed on a side of your house that has a tendency for high winds, installing small angle brackets on the lid on the left and right side of the lid opening prevents the downspout from shifting in high winds.

7.  Be aware of the type of lid on the barrel.  Some lids are concave and some are convex.  I prefer the convex type to minimize ponding on the lid and it gives you a little space between the lid and the screen.


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