Introduction: Mini Bucket Rain Chain
During lockdown my husband and I roofed over an L-shaped area at the back of our house to provide a covered outdoor space. The gutters serving the two legs of the roof discharge at a common point which – through sheer bad planning - is several feet away from the nearest surface water drain. So what to do? Then I had a brainwave, remembering a rain chain I’d seen at a friend’s house in Switzerland some years ago, and a recent meal in a trendy pub where the chips accompanying my burger were served in little metal buckets.
Rain chains are a decorative alternative to a fall pipe or downpipe – the vertical pipe that takes rainwater from the low point of a gutter to ground level where it’s discharged into a drain or soakaway. Although rare in the UK, they’re hugely popular in certain other countries, especially Japan. The water flows down the chain, limiting the amount of splashing while avoiding the need for a rigid pipe.
A rain chain can be as simple as just a chain but often they have metal tubes, flowers or other shapes suspended at intervals down the chain which help to funnel the water as well as looking beautiful (and rather Zen). This was the kind I wanted to make, because I certainly wasn’t going to spend £100s on an imported Japanese rain chain. Read on to discover how I did it, for a total cost of under £30 for a 2.5m rain chain.
- Rustless chain with a link size of about 9-10mm wide x 15-20mm long (eg this stainless chain from Toolstation)
- 15 mini stainless steel “presentation buckets” (see Step 1) from a catering equipment supplier (eg. these, or these slightly smaller ones)
- Approx 150-300 mm of heavy gauge rustproof wire (I used a giant paperclip)
- A drill and 10mm HSS bit (or whatever bit size suits your chain), plus a small bit for a pilot hole
- A centre punch (or a small nail) and a hammer
- A round or half-round needle file
Step 1: Choosing a Bucket and Chain
The first thing to consider is the quantity of water the rain chain needs to handle. Mine is serving a roof with an equivalent horizontal area of about 12.5m², for which the chain and buckets suggested under Supplies are of adequate size. (My buckets measure 55mm high not including the handle, top diameter 70mm, bottom diameter 50mm.)
You may need to go up a size for a house roof. A standard fall pipe in the UK is 68mm diameter. Be guided by the size of your existing fall pipe, or the size recommended for your size of guttering if this is a new installation. Buy buckets that are approximately the same diameter as the fall pipe, and chain that is in proportion - not so big that it occupies a lot of the bucket volume.
The presentation buckets I bought are meant for serving the tomato ketchup, etc that goes with a burger in a trendy eatery. A size larger is available for serving chips (aka French fries) which should be suitable for bigger roofs, and there are even bigger ones intended for storing cutlery on the table. You can find copper buckets too if you search, which would look great with copper chain.
You also need to think about the weight of the finished rain chain because, unlike a fall pipe, it’s suspended from the gutter with no additional support from the building or the ground. The buckets don’t weigh much (mine are 30g each), and I used a fairly slim chain, but a chunky one would be much heavier. Before deciding on the number of buckets and the chain you’ll use, weigh a bucket filled with water (I assumed that every bucket would be full in heavy rain, which is unlikely to be true, but I didn’t add anything extra for water on the chain itself), multiply by the proposed number of buckets and add on the weight of the chain, then check that your gutter is well enough fixed to take the load. The total weight came to 2.5kg in my case, not enough to worry about.
I used stainless steel buckets and aluminium chain, because I don’t want my rain chain to rust. Galvanised steel buckets and chain are easier to come by and will rust eventually, but that could look quite charming in a rustic, farmyardy sort of a way. I found the tiny stainless buckets in two styles (linked under Supplies in the Intro), one of which is smooth and modern-looking, but I went with the style that’s like a traditional garden pail. Not only is it more interesting in my view, but it looked from the photos on suppliers’ websites like the handle might be harder to remove on the other type, and those handles didn't have a little kink in the middle to keep the buckets hanging upright on the chain. Also, the pail is a near match for my blue garden bucket which I might put at the bottom of the rain chain in the summer.
Step 2: Chain Length and Bucket Spacing
Do you want your rain chain to reach the ground, or will you place a rainwater butt, plant tub or gravel-filled container under it? Measure the drop from immediately under the gutter and buy enough chain for that, plus a little extra.
Bucket spacing is to some extent a matter of aesthetics, although the more of the chain that is within buckets the less splashing and loss of water from the chain there should be. As a starting point, work on the basis that (ignoring the handles) the gap between each pair of buckets should be about the same as the height of a bucket. The buckets I chose have a handle that’s about half as tall as the bucket when it’s fully raised, and I adjusted the spacing of my rain chain so that the suspension point (ie the top of the handle) for a bucket is roughly half way up the gap to the next bucket.
To help me decide if this was right, I did two things. First, I cut up a length of plastic drain pipe into three pieces and drilled holes across the diameter at the top so I could suspend them from the chain using garden wire. I tried this dummy rain chain for a few days at a time, with various spacings, to see how it performed in light and heavy rain. (You could always pour water into your gutter with a hosepipe if you're doing this in a dry spell.) I concluded that whether the spacing gave 50% chain coverage or only 25% didn't make a big difference to how well it handled the flow, it seems to be the chain that is doing all the work rather than the "buckets". But this did give me confidence that the mini buckets I was planning to buy - which were a similar diameter to the pipe - would work.
Second, I mocked up an image in Gimp of a rain chain with a tight spacing and a wider one. You could do the same using bucket and chain images from suppliers’ websites.
When you’ve decided on the spacing, work out how many buckets you need. I should buy an extra one, just in case.
Step 3: Drilling Holes for the Chain
There needs to be a hole in the bottom of each bucket through which the chain can pass. How big it should be depends on how big a flowrate your rain chain will have to cope with, and whether you want all the water to run down the chain inside the buckets or whether you’d like them to fill up and weir down the outside in heavy rain (think Champagne fountain!). I suggest starting with a hole that is only a little bigger than the width of a chain link. When you’ve had the rain chain up for a few weeks and have seen how it performs in different levels of rainfall, you can always take it down and enlarge the holes if necessary.
The holes are best drilled from the outside in, because the underside of the buckets will be visible. To mark the hole location, cut a disk of paper that just fits in the base of an upturned bucket. Fold it in half twice to find the centre.
My buckets have a little flange on each side of the top through which the handle ends pass. I didn’t want to risk bending these flanges, so I found a small plastic container with an outside diameter slightly less than the inside of the bucket base. I placed some scrap plywood on the container then upturned each bucket in turn on it so I could mark the base through the paper disk with a centre punch without distorting the metal unduly.
Next I drilled a pilot hole, then a larger hole, in the base of each bucket with it supported in the same way.
Remove any burrs and sharp edges with a needle file, and use the file to enlarge any holes that are too tight. If the chain catches on the edges of a hole, the bucket won't hang straight.
Step 4: Hanging the Buckets on the Chain
I found I could spring the bucket handles free with my fingers if the handle was lying flat along the top rim of the bucket. But if necessary, use pliers (pad the jaws with a rag to prevent scratching) to gently bend one end of the handle so it can be released.
Start with the uppermost bucket. Feed the top end of the chain through the hole in the bucket, from the bottom up, then push the free end of the handle through a link of chain that’s the appropriate distance from the top end. Treat that end as if it were the base of a bucket, so your first bucket needs to be the usual spacing below it, but add a few inches (this excess can always be cut off afterwards in needed), then choose the link that is to be the handle suspension point wherever is necessary to achieve that. Spring the handle end back into position.
The next part is easier if you can hang the chain up temporarily. Count how many chain links there are between where the top of the chain ought to be (ie subtract the extra length that was added previously) and where the bucket handle is attached. Count this number of links down from the base of the first bucket and hang the second bucket from there. Repeat with the remaining buckets, all the way down the chain, but hang the chain up somewhere temporarily when you have 6 or 7 buckets on it. Stand back and have a look to check that you're happy with the spacing before you go any further.
I've only used 11 of the 15 little buckets I bought so far. But I'll need the others if I take my rain chain right down to the ground instead of ending it over a tub, and I may yet reduce the spacing.
Step 5: Suspending the Rain Chain
An existing gutter probably has a stopend outlet at its lowest point, ie a blanked-off end with a round spigot pointing downwards which goes into the top end of the fall pipe. The simplest thing to do is to use pliers to bend a length of wire into a V-shape with legs at the top to stop it falling down the spigot. Ideally, the bottom of the V should be an inch or two above the lower end of the spigot, so that the wire isn’t visible from the ground. (Which is why an extra few inches were added above the top bucket in the previous step.)
If this is a new gutter, you could just fit an ordinary stopend and use a holecutter to make a hole in the underside of the gutter close to the end. The bottom of the V-shaped piece of wire will inevitably protrude through the hole, so don’t make the V any deeper than it has to be.
My canopy gutters were small (about 48mm diameter), and I found a plastic pipe which just fitted over them. I used this pipe as a gutter extension and drilled a hole in the underside.
However you do it, feed the top end of the chain up through the spigot or hole into the gutter, then feed the V-shaped wire through the top link. Position the legs of the wire so that it can’t fall down the hole, and make sure the legs are as horizontal as possible to minimise the chances of leaves and other debris catching in them and causing a blockage.
Then all you need to do is wait for rain.
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