Note: If you have cast iron downpipes, making the connection will be very difficult, so upgrade to plastic or don’t attempt it.


A good example of a water butt can be made from a downpipe selected from your guttering. Cut the pipe and then direct it straight into the top of the water butt itself which is done with the aid of a rain diverter that should be supplied with the kit that you have purchased.

Run an overflow pipe from the top of the butt and reconnect to the base of the downpipe. Note: If you are using the diverter you may find that an overflow is not necessary and providing the diverter is fitted lower than the top of your water butt it will stop filling as soon as it is full. The majority of water butts are supplied with instructions and all the information and parts that you will need. The tools that you need are a tape measure, hole cutter and a drill. Regents Park Plumbers can fit water butts.

There is no standard shape and size of downpipe so it is possible that the kit provided may not work. Most merchants stock a great choice of pipework, so either pull off an existing connector (most are push fit) and take it with you or measure the external diameter yourself and try and find one. Square shaped pipes are easy to measure but for round you will need calipers or string and a rule. Pull the string around the pipe and mark the two ends where they meet. Note this measurement. You need to divide the measurement by 3.1

4 (PI). A Regents Park Plumber can make this calculation. The resulting number gives you the external diameter of the pipe. You need to ensure that the inlet and overflow pipes are approximately the same size. If not the butt can overflow if it is subject to severe rainfall. The majority of these kits can resolve this by supplying an inlet that will only collect small amounts of water. There is a temptation to try and collect all the water, especially if you have a large butt and the water is coming off a fairly small area, but if you do this you must adjust the overflow accordingly.