Taps– Selection Criteria

What is an efficient tap?

As heating hot water represents about 17% of total typical household energy use, it’s good to consider whether water efficient taps that can help reduce the volume of hot water we use.

Our Taps category contains two main types of products that can help you to achieve reduced hot water use: flow regulators and mixer taps.

To find out more about these products, see our Product Guide.

Introduction

This page details the selection criteria applied to taps on toptenuk.org. Efficient taps provide savings by reducing the volume of water used and consequently reducing the hot water demand. The voluntary Unified Water Label provides the basis for topten selection criteria.

Selection Criteria

The minimum criteria to be shown on toptenuk.org are shown below:

Top efficiency class (dark green arrow) according to the Unified Water Label
Listed on the official product database of the Unified Water Label

Relevant Guidance

The following regulations were the basis for the above selection criteria for taps.

Regulations

There are currently no regulations that cover taps.

Unified Water Label

The products on the Topten website all have to achieve the top rating (dark green arrow) based on the the Unified Water Label. This rating is purely based on the flow rate of the appliance with the bands given in Figure 1. The energy label is shown in Figure 2 presents the energy band, actual flow rate, annual energy usage and shows the product feature icons.

Figure 1: Flow rate categories for taps (Source) & Figure 2: Example Energy Label.

Annual energy consumption

The energy consumption per year is based on fixed assumption on consumer behaviour and calculated with the Energy Calculator from the Unified Water Label. Calculations in the energy calculator are based on the following assumptions:

Washbasin taps: 5 uses per day, 1 min each
Kitchen taps: 5 uses per day, 1 min each
Conditions:
- Cold water inlet temperature: 15 °C
- Hot water output temperature:
  - 38°C (showers, basin taps)
  - 45°C (kitchen taps)

Product data must be measured and declared according to the Unified Water Label.

The project will assess the option of calculating and adding the yearly water consumption and cost to the product data on Topten as well as energy and water cost savings compared to a similar model of a lower class.

Glossary

Flow regulators: Small items that can be installed between the fitting and hose or at the outlet of a tap that reduces the water flow through the appliance. Alternative term: controller.
Mixer tap: A tap that allows for continuous flow and heat settings. Used for basins, kitchens and showers.
Sensor faucet: a faucet without manual regulator where a sensor turns the water on and off. This can save up to 70% of hot water.

Taps Selection Criteria