Galvanized steel potable water supply and distribution pipes are commonly found with nominal pipe sizes from 3?8 inch (9.5 mm) to 2 inches (51 mm). It is rarely used today for new construction residential plumbing.
Steel pipe has National Pipe Thread (NPT) standard tapered male threads, which connect with female tapered threads on elbows, tees, couplers, valves, and other fittings.Galvanized steel (often known simply as "galv" or "iron" in the plumbing trade) is relatively expensive, and difficult to work with due to weight and requirement of a pipe threader.It remains in common use for repair of existing "galv" systems and to satisfy building code non-combustibility requirements typically found in hotels, apartment buildings and other commercial applications.It is also extremely durable and resistant to mechanical abuse. Black lacquered steel pipe is the most widely used pipe material for fire sprinklers and natural gas. Źródło: https://en.wikipedia.org/wiki/Plumbing
A boiler is a closed vessel in which water or other fluid is heated.The fluid does not necessarily boil.(In North America the term "furnace" is normally used if the purpose is not actually to boil the fluid.) The heated or vaporized fluid exits the boiler for use in various processes or heating applications,12 including water heating, central heating, boiler-based power generation, cooking, and sanitationŹródło: https://en.wikipedia.org/wiki/Boiler
They can be rented during the construction of the house.
They also participate in the process of putting up apartment buildings and schools of all sizes.
It seems that the least complicated plumbing services are performed in the course of construction of the house, because they are limited to the performance of domestic water supply and sewage, and in the case of apartment blocks need to make a detailed plan of such a network adequate to the number and position of the individual apartments.However, in the case of schools you need to equip the bathroom in the right amount of sinks, where you will be able to wash their hands after using the toilet. In schools, sports can also stand up showers..