Why taps waste so much water

A normal tap aerator does not restrict flow. Water output depends on line pressure, so a typical tap delivers anywhere between 8 and 15 litres per minute. During a hand wash, most of that water simply bounces off the hands and goes down the drain.

A water saving nozzle or aerator fixes this by breaking the stream into fine droplets or mixing it with air, and by limiting the flow to a set rate. Users still feel a full, usable stream, but the tap uses a fraction of the water. Depending on the model, the saving can be very large; some mist nozzles from the Greenly range restrict flow to around 300 ml per minute.

Because the savings come from every single use, high-traffic taps give the fastest return. Washrooms in offices, factories, malls and hostels, where many people use the same tap all day, are the best places to start.

Nozzle or aerator: what is the difference?

In everyday use the terms overlap, but there is a practical difference. A water saving aerator is usually a mesh or insert type device that fits inside or on the tap mouth and gives a shower, laminar, aerated or mist flow.

A water saving nozzle is a more robust attachment that screws onto the tap thread and shapes the water into patterns such as shower, umbrella (hollow cone) or mist. Nozzles from the Greenly range are made of brass with CP coating, which makes them a good choice for high-use public and commercial taps.

Choose the flow rate for each tap

The most common mistake is fitting the same low-flow device on every tap. A wash basin and a kitchen sink do very different jobs, so they need different flow rates. Use this as a starting point:

• Mist flow is not suitable for kitchen sinks, where you need volume to fill vessels and wash utensils.
• Where water demand is higher, go one step up in flow rather than frustrating users.

Understand the flow patterns

Flow pattern affects both comfort and saving. Mist flow breaks water into very fine particles and gives the highest saving, which works well for hand washing in offices. Shower flow spreads the water into small streams and feels natural for most users.

Umbrella flow creates a hollow cone that covers a wider area with little water. Laminar flow gives a non-splashing solid stream, and aerated flow mixes air into the water for a soft, splash-free stream at higher volumes. Some nozzles, such as TrueMist Twister, switch between mist and shower modes, which is useful where one tap serves two purposes.

Check thread size and tap type

Before you order, check how the device will fit. Standard Greenly water saving nozzles have an M24 outer thread, and adapter rings are available for taps with an M22 thread. Standard aerators fit most Indian taps with a 22 mm nozzle diameter, using male or female brass adapter rings.

If your tap has an unusual size, a customised nozzle may be possible. If the tap has no thread at all, a tap flow controller or restrictor is an option, though replacing the tap is often the better long-term solution. Also note the water supply: these nozzles work on both pressurised systems with a booster pump and gravity-fed systems.

Material, warranty and maintenance

Material decides how long the device lasts. Greenly water saving nozzles are made fully of brass with CP coating and carry a 2 year replacement warranty. Greenly aerators are made of POM (polyoxymethylene), an engineering plastic, and carry a 1 year replacement warranty against breakage.

All aerators and nozzles need occasional cleaning, because sand, scale and particles build up on the screen and reduce flow. Remove the device, rinse it and soak it in a vinegar and water solution if there is limescale. It is advisable to replace tap aerators about every 2 years for consistent performance.

What to send us for a quotation

For an office, hotel, school or factory in Ahmedabad or elsewhere in Gujarat, a short tap survey makes the quotation accurate. List the tap locations, how many taps of each type, and a photo of each tap mouth.

Mention the thread type if you know it, whether the supply is pressurised or gravity-fed, and the main use at each point. We will recommend a flow rate and pattern for each location and quote the right mix of nozzles, aerators and adapters.