Byelaw 30 kits and Byelaw 60 kits consist of a set of components designed to protect the water in a cistern from contamination. They are intended for potable water cisterns, such as the cold water storage cistern in the loft. Byelaw 30 kits often come with new cisterns. However, they can be purchased separately if one is looking to upgrade an existing installation. The variation in name is due to the separate legal systems in the UK, namely England and Wales, and Scotland. The main difference between the two kits is the diameter of the overflow. The Scottish Byelaw 60 stipulates a larger diameter overflow.
The kits generally consist of a screened overflow pipe, an overflow dip tube, a rubber grommet for the expansion/vent pipe, and a breather fitting. Along with the cistern lid, they are vital in keeping the water in the cistern free from dirt and debris. Depending on the manufacturer, some kits may include a Part 2 ball valve and/or a small ball valve backing plate.
Byelaw 30 and byelaw 60 kits
The cold water storage cistern is a key part of your plumbing system. Without any protection, foreign objects such as dust, loft insulation and insects can get inside. In some cases, even rodents and birds may fall in, if they can get into your loft. Byelaw 30 and byelaw 60 kits are vital for protecting your system from blockages and contamination. They typically include the following items:
- A rubber grommet, to create a sealed admission point for the expansion pipe/vent pipe.
- A screened breather, fitted into the lid in order to prevent the formation of condensation inside the cistern and keep it at atmospheric pressure.
- A screened overflow pipe, to prevent anything outside, such as insects, from entering the cistern.
- A dip tube, allowing the overflow pipe to dip into the water so that cold drafts cannot enter the cistern.
The difference stipulated by the different codes is that the overflow dip tube must be 38mm (1.5 inch) in order to satisfy Byelaw 60 in Scotland, whereas 22mm (3/4 inch) is suitable for Byelaw 30 in England and Wales.
Water regulations also require that cisterns have a close-fitting lid. The lid must be made from a material which will not react with the water, and will retain its structural integrity even if it gets wet.
Some byelaw kits may include a small plastic backing plate. This is secured to the out cistern wall via a nut on the stem of the ball valve. Its job is to reduce the stress on the cistern wall from the upward force of the float. Some byelaw kits may include a ball valve – usually a Part 2 model.