What is the recommended hot water temperature for a kitchen sink or wash basin?

55 °C is the recommended temperature at the tap, as per Table 2.

How much hot water storage is needed for a small house?

For a dwelling with 1 bath, 1 sink, and 3 wash basins, a storage capacity of 115 litres is recommended in Table 1.

What is the estimated hot water demand for a single shower?

The demand for a single use of a separate shower is estimated between 45 and 70 litres according to Table 3.

What is the purpose of the temperature and pressure relief valve?

It's a critical safety device (Clause 7.2) designed to open and discharge water if the temperature exceeds 100°C or pressure becomes excessive, preventing tank explosion.

IS 7558

: 1974

Code of practice for domestic hot water installations

CurrentFrequently UsedCode of PracticeBIMMEP · Public Health Engineering

Download PDF BIS Portal Google

This code of practice provides guidelines for the design and installation of domestic hot water systems in buildings. It covers aspects like sizing of water heaters and storage tanks, pipework design, material selection, and necessary safety controls. The standard aims to ensure an adequate and safe supply of hot water for various domestic uses.

Code of practice for domestic hot water installations

Quick Reference Values

Recommended tap temperature for bath/wash basin55 °C

Recommended storage for a small dwelling (1 bath, 1 sink, 3 basins)115 litres

Hot water demand per bath use90 litres

Hot water demand per shower use45-70 litres

Safety device operating temperature limit100 °C

Practical Notes

This code is from 1974; always cross-reference its provisions with the latest National Building Code (NBC) of India, particularly Part 9: Plumbing Services, for modern practices.

Pay close attention to insulation requirements (Clause 6), as it's crucial for energy efficiency and often overlooked in smaller installations.

The demand values in the tables are a starting point; modern low-flow fixtures or luxury high-flow fixtures may require adjustments to these decades-old assumptions.