The second part of the article focuses particularly on water and gas supply plumbing. For the water supply plumbing the current need for metering must be taken into account and the location of the meters resolved. Changes occurred also in the pipelines and materials. Old gas supply lines can be problematic in terms of the dimensions and tightness of the pipelines. There will be vital changes in the requirements for the location of main valve and gas meters. The renovations will require the most accurate survey and carefully prepared project. In order to have a successful renovation, improvisation in the construction works must be most limited.

The renovation of the so called "Panel Buildings" is currently the centre of attention. This creates the impression that renovation and modernisation are only necessary for this type of buildings, while others, often much older blocks of flats, are not in need of renovations. The renovation of the sanitary installations in old brick buildings is often much more difficult because the ascenders and waste pipes are not located in shafts. Most pipes are right under the plaster or under the floors on underground floors. The materials of plumbings that can be found in these buildings are gradually reaching the end of their lifespan. In buildings dating from before WWII we often come across obsolete and usually unsatisfactory lay-outs for the sanitary installations.

Separation of yellow waste water and rainwater, and their subsequent use in agriculture (yellow water) and residential (rainwater) is real. When using tank rainwater, tanks to stabilize urine and domestic wastewater treatment plant we will have 85% savings in potable water.

The article deals with the influence of the floor area of house energy supplied to the hot water. Mutually compare three methods of calculation and one of them use in the calculation of delivered energy for hot water system, through which energy class is designed for local consumption - the warm water.