Why an attic space is one of the requirements is the presence of a water and sanitary system up to standard.
If you want to add a health more in the attic or if you want to install a new water and sanitary system in the design phase you will need to conduct an accurate survey of the actual state of the pillars of supply and exhaust the whole building.
If the attic is already a bathroom with a drain pipe this can be the starting point for a new water and sanitary system.
If there is neither drinking water nor a drain pipe you will need to hook into the waste stacks of floors below and not build a new one because it would be too complicated and expensive. If the amount of water does not reach the attic you will need to take action to make it so by changing the final stretch of the column. The size of the column is in relation to the discharge unit which is to serve, so it will take a unit for each sink, two for the shower and bidet, three for the bath, five for the pot of toilet and so on. When you find the point where you will need to connect the new facility to design the most suitable location for the toilets and the kitchen.
We know that the attic has a special because of the roof to which the Plumbing should be studied taking into account this problem.
An intelligent device is to place the toilets in areas of eaves ie where there is a height of the roof lower, thus building the new bath in the vicinity of the p areti perimeter , in this case a gap will be created to accommodate the branches exhaust. Finally, in the design phase, studies of solutions such that the spaces in which are present Plumbing is everyone equipped with a ventilation system up to standard.