Floating ideas on rain barrels

I keep watering a lot because the lettuces growing in our back porch planters are thirsty. That is one of the drawbacks of planters. They don’t have much of a moisture reservoir and need water once, sometimes twice a day.

I was done schepping the watering cans out of the basement and decided that a new set of rain barrels would make my watering chores much easier. Plus they would convert a waste product (roof runoff) into a useful resource (water for irrigation).

Yet the how-to on rain barrels hasn’t quite trickled into our general knowledge base. I constantly run into this when speaking at conferences about rainwater harvesting options. Rain barrels seem so simple, yet it actually require some thought to get them right.

Raison d’être

Harvesting roof runoff and/or mitigating the impact of stormwater runoff is the primary function of rain barrels. That said, they can quickly become a white elephant, unless you plan to actively use them. In other words, you have a need for the harvested water, and/or it is likely that you draw the rain barrels empty on a frequent basis.

Some municipalities have rain barrel programs, which I mostly regard as well intended but not that helpful. The hope is that the rain barrels store some runoff and keep it out of the overtaxed stormwater system. Yet I noticed that most of those rain barrels, once installed, serve as mere decoration, and the stored water is not used or drained. The barrels sit there full with water for most of the warm season, which completely negates any intended runoff mitigation.


Say you have a good use for rain barrels or are willing to drain them between storms. What would be the contributing area (i.e. the size of the roof) that would feed into the rain barrels?

If you have a small bike shed with a couple of 55 gallon rain barrels connected to it, you may have to wait for quite a while before they fill up. Conversely, if you have a couple of rain barrels connected to a 2000 square foot roof, they may fill up in the blink of an eye.


For rain barrels to provide any runoff mitigation benefits, their storage volume should be sized proportionally to the contributing roof area. For example, say they can store a quarter or half inch of rain fall on the contributing roof area. This may be more volume than you need for irrigation. In this case the barrels should be drained prior to approaching storms, to free up the storage volume.


How do you get the water from the gutter and downspout into the rain barrels? These days you can find a variety of downspout diverters that solve that problem for you. The better ones have a built in filter that keeps debris out. The really fancy ones even have a winter bypass.

I used a homemade diverter and filter on our early rain barrels. It was not pretty, ideal or long lasting, but it did the job at the time.


Most rain barrel products come prepared with plumbing connections. But not all of them make sense. Here are some things to look out for:

If more than one barrel is needed, make sure they are connected to each other at the very bottom. You may have several barrels, but this way you have one storage volume. It allows you to access that entire storage volume from any barrel, and it will allow you to drain all barrels at once, which is important for winterizing.


Go with a product that has the faucet to draw water from the barrel at the very bottom, not one third or half way up. If the faucet is not at the very bottom, you never can effectively use all of the stored water, or completely drain the barrels between storms or for winterizing purposes.


Set the rain barrels on a pedestal. This would allow you to fit a watering can or bucket under the faucet, even if it is at the very bottom of the barrel.


Well, this is really part of the plumbing, but it deserves a special mention.

Your rain barrel(s) will be full at some point. If it continues raining, you have to have a plan on how to deal with the overflow. A lot of people don’t and inadvertently create flooding issues where there previously were none.

For a starter, make sure the rain barrels have an overflow pipe somewhere at the top. That overflow pipe should be the same size as the supply pipe that is delivering water into the rain barrels. Under no circumstances should the overflow be smaller than the supply.


Rain barrels are often placed right next to the house – next to a downspout. Have a plan on how to divert the overflow a safe distance away from the house and thus keep your basement foundation dry. A swale, a pipe extension or a channel could do that job.


If you are in a freezing climate, you need to winterize your rain barrels. That means they need to be completely drained during the freezing months. In addition, you have to disconnect the downspout diverter so no water is fed into the rain barrel(s). If you have a fancy diverter, you will need to put it into winter bypass mode, which should keep runoff out of your barrels.

If you fail do any of the above, or miss one of those steps, you are likely to become a proud owner of a giant ice cube … an ice cube that will make your barrels burst or crack.

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Salad bar

It was April. I had planters on my back porch railing. And I had ideas on what to plant in them.

How about trailing annuals that would cascade over the edge of the planter and provide a curtain of blooms across the railing during the summer? What a delicious sight would that be!

Talking about delicious, how about something that would not just be a feast for the eye but also for the tummy?

I’ll make it short: the prospect of growing something edible in those planters won over the vision of cascading blooms.

We had been growing vegetables in our small raised planter over the past couple of years. Well, I say we, but Cathy deserves the credit. What we shared, though, was the frustration that our lettuces all bolted before they got a chance to grow into nice heads that could be harvested. They bolted because by the time they were beyond the seedling stage, we had entered the hot season. And just in case you don’t know, lettuces don’t like it hot. They are cool season plants.

With the back porch finished and planters on the railing, I saw an opening to sneak in a cool season crop. I seeded the planters with lettuces in early April. The few nights when we had frost, I moved the planters and sheltered them in the enclosed basement part of our back porch. This way, we got to grow our first crop of lettuces before it got too hot. And they were looking great!


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Back porch planters

My thumbs were itching! The green part of my thumbs, to be precise. Must be neurological, because my mind was seeing something that must have caused that itch…

A couple of years ago, Cathy put a raised planter together to start our small scale, yet delicious and appreciated vegetable production.

Last year, we put our back porch together, with access to the roof where we are eventually planning to have our vegetable garden. But all my mind was seeing was railings – railings that screamed: “hang a planter on me”!


I had to make that itch stop. I decided to obey the call, and act.

So I got myself some hardware, brackets and lumber. I put the brackets up on the porch and railing posts and mounted a two by six onto them. This was the shelf that would hold the planters.

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To prevent the planter from sliding off, I took a small piece of board and attached it to the outer edge of the shelf. The board will act as a stop. I also drilled some drain holes into the shelf bottom.

Of course I knew the planter size before I started and dimensioned the brackets and shelves accordingly. And I was hoping that the whole assembly would be sturdy enough to hold the planters.

The best way to find out was to fill the planters with potting soil, soak them, and put them on the shelves.

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Yep, it’s holding up OK! Yet, I still have the green part of my thumb itching. May be I should plant something?

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Sump pit lid

It’s down to the finishing touches on the back porch enclosure. And to make it not just user friendly but also safe, I had to get a lid for the sump pit – a gas-tight lid to prevent moisture and potential radon from diffusing.


There were a number of lid options out there, and I probably have been looking at most of them. But I am a cheapskate and those lids were expensive. That may be because some of them have a vehicular traffic rating, which we really didn’t need. Foot traffic is all this lid will see.

Because I didn’t want to reach deep into my pocket, I decided that a three quarter inch plywood cover should do. But how would I fit it onto the pit without creating a trip hazard?

Well, we cut out a one inch wide ledge from the upper most concrete adjustment ring. And we made it just deep enough so it would accommodate the three quarter inch plywood cover.

To prevent mold from growing on the bottom of the the cover I attached two layers of a 6 mil poly sheet. Those sheets will also serve as a vapor barrier. And to make the system gas-tight, I grabbed a neoprene gasket and installed it on the ledge. The plywood cover, which was now flush with the floor, is held down by six screws.

Cutting out the ledge was tricky, yet fairly easy thanks to the great help of our friend Rubani!

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Porch enclosure – stair insulation

I am obsessed with insulation. And in case you haven’t noticed, let me tell you about the stair insulation in the back porch. The perfect hybrid between ceiling and wall insulation: a combination of cut-and-cobble and some fluffy rock wool.

To address the air sealing, I again had to rely on cut-and-cobble pieces of XPS insulation underneath the stairs. And like with the ceiling, I carefully foamed around and between the pieces.

Back-porch-52 Back-porch-53

I had the idea of filling the space between the installed XPS and the bottom of the stair stringer with rock wool. Our rock wool batts that typically are installed in a framed wall were not really suitable here. But I found several bags of loose rock wool at my favorite gold mine, the Rebuilding Exchange.


To find a way around gravity, and to add an extra layer of insulation, I attached another sheet of XPS insulation to the bottom of the stair stringers. That allowed me to stuff the space with the loose rock wool without it falling down.

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Well, with that done, I can start to think about drywall and painting!

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