In multi dwelling residential projects, toilets and kitchens are stacked one over the other in respective floors and are supplied with single header each for potable & recycled water supply (wherever applicable).
Taking an example of a 2 bedroom apartment with 2 toilets and 1 kitchen, will have 3 supply connection one each in toilet and kitchen for potable water & 2 supply connection one each in toilet for recycled water. Also there are separate supply headers for hot water. To meter the same and have meters will translate to a requirement for putting 5-6 meters which is not a practical solution and hence metering for water should only be proposed at building level and not at floor / apartment level as this will never be executed by any project.
If the project chooses to demonstrate compliance with clause 28.1.2 for 2 points, then the project has to comply with all extended metering requirements as mentioned in the table, which includes the provision of water meters at apartment level. Please note, it is recommended to adopt the GRIHA methodology in the early design stage to not only improve project efficiency but also reduce overhead costs.