FAQ's

Frequently Asked Questions

WELS stands for Water Efficiency Labelling Scheme. When building or renovating, it's important to understand your water pressure system and how water efficient your bathroomware is. In general, New Zealand homes have low/unequal pressure. Newer homes are mains pressure, which allows multiple water outlets to be used simultaneously without reducing pressure. Bathroom products are given a WELS rating to help you choose based on your home's needs. More stars indicate lower water usage. For more information, click here.

WELS Star Rating Example

S-Trap systems are ideal for new homes with the waste outlet going through the floor. The distance between the waste outlet and the wall is the set-out measurement. To view S-Trap toilet systems, click here.

P-Trap systems have a waste outlet that goes through the wall and are common in bathroom renovations, featuring a standard 185mm set out. To view P-Trap toilet systems, click here.

Many New Zealand homes have low or unequal water pressure systems. If your cold water flow is greater than the hot, you likely have a low/unequal pressure system. Your hot water cylinder may be marked 3.7m (12ft) or 7.6m (24ft) HEAD. Older homes often need tapware to balance the higher cold flow. Low pressure is usually supplied by a header tank or a pressure reducing valve. An equal mains pressure system is common in many homes today.

Mains Pressure (High) provides both hot and cold water at high pressure. Cold water comes from town supply, while hot water is supplied by a high-pressure cylinder or gas infinity.

Cold water comes from town supply or tank pump (approximately 500kPa). Hot water comes from a low pressure hot water cylinder. 'All Pressure' Tapware is suitable for Unequal Pressure systems.

Both hot and cold water are supplied from the same source at low pressure (e.g., header tank/gravity feed). 'All Pressure' Tapware is suitable. If you have a hot water cylinder with a metal pipe protruding from the roof, you likely have low pressure hot water. An easy test is to turn both hot and cold to full and compare their flow rates.

Download our Bathroom Planner to start selecting products that fit your home, family, budget, and lifestyle.

Bathroom Planner

About Plumbing World

With nationwide branches from Kerikeri to Invercargill, Plumbing World is New Zealand's largest 100% locally owned plumbing merchant. We offer a wide range of quality products, including exclusive brands, and provide personalized service from our experienced staff. Find out more about us here.