Plumbing Riser Design for Water Supply Systems in Plumber


Once one or more Water Supply Systems has been created in Plumber, is also possible to carry out the design (or calculation) of the vertical distribution pipe or Plumbing Riser.

Be the supply configuration across the Plumbing Riser in ascending or descending form, the geometrical configuration is the same: a vertical pipe with an outlet (or more) at each level or story of the building to supply one or more Water Supply Systems that not necessarily will have the same characteristics.

In Plumber, the Plumbing Riser modeling for the Water Supply System is performed considering the following:

  • Riser has a “Source” node where, as in the case of internal water supply network design, the minimum required pressure (design option) will be calculated to meet the pressure at the inlet of the most unfavorable water network in the Building. For the calculation option, is in the source node where user will specify a pressure so that the program can determine the supply pressure at each level.
  • At remaining nodes, must be specified amount and type of one or more types of Water Supply Systems available in the project and which are expected to be supplied from that node. Additionally, each node must have in this case an elevation, corresponding to the different levels (stories) in the building’s water supply system.
At design time, Plumber will determine which of all Water Supply Systems served by each riser node has the highest required pressure in its supply node in order to use this value in determining the required minimum pressure at Plumbing Riser “Source” Node.

Building the Drinking Water Plumbing Riser in Plumber

We will use the typical installation that we created in this example and will consider that the Plumbing Riser is of ascending type, and serves a 4-story building:

Example-for-Plumbing-riser-calculation

Note that the Plumbing Riser will supply two Water Supply Systems at levels 2 and 4, while only one at levels 1 and 3.

Adding Nodes to the Plumbing Riser

The dialogues available are similar to those that we saw in this article, with the difference that in the case of the Plumbing Riser will not be available the buttons and commands to add pipes to hot water system.

So, when you access to the Riser tab in the Plumber’s Main Window, you’ll find three tables: The Nodes table called Attended Water Networks, the Pipes table and the diameters table, which presents fixture units, probable flow and calculated diameters for each pipe section. This last table is not directly editable (is a table of results).

In Attended Water Networks table will be presented, by default, a Node: the Plumbing Riser Source, which cannot be removed from the project. Placing us in the respective file and pressing the Edit button of the Networks Panel in Project tab, will see the Plumbing Riser Nodes Editor:

Plumbing Riser Nodes Editor

Here you can change name, elevation and establish whether you are in the design condition (Pressure Calculation check box checked) or in the calculation condition (Pressure Calculation check box unchecked) in which case will be visible a text box to enter the pressure in this source node.

Pressing the New button in the Networks Panel and ensuring of having active the Riser Tab, will be presented the Nodes Editor but with additional information:

Adding-a-new-node-to-building-plumbing-riser

among which is the list of available Water Supply Networks in the project, from where will be selected those installations that will be attended (supplied) by this node.

In the example there is only a Water Supply System at this Node (level 1), so the editor view will be similar to this:

First-Node-in-plumbing-riser-example

When click OK button, will be shown, in the Attended Water Networks table, the new node created. Similarly add the information of the remaining stories or building’s levels, to have this final view:

Table-of-Attended-Water-Networks-by-Plumbing-Riser

All Plumbing Riser nodes (except the source node) must have assigned at least one Water Supply Network. Otherwise, Plumber will inform to the user to make further modifications.

Creating Plumbing Riser Pipes

Pressing the New button, in the Cold Water Pipes Panel, Pipe Data Editor dialog will be shown. In this dialog will be indicated: the start and end node labels (taking into account flow’s direction: initial node is located upstream and the final node is located downstream of the pipe section), if we want Plumber to calculate the diameters or not (Diam. Calculation check box), and, pressing the Lengths button, we can indicate the length of pipe and fittings installed in this pipe section. Also, when flush valves fixtures are present in water supply network, Supplies Fixtures with Flush Valves check box must be checked.

Adding-Pipes-to-the-Plumbing-Riser

By default, when you create a new pipe, a Tee is assigned to its installed fittings list, which is necessary to supply the appropriate level (Node) and continue the Plumbing Riser journey to following levels.

Creating the remaining Plumbing Riser pipes, we will have this table:

Riser-Pipes-Table

This is all the information needed for the Riser design and calculation with Plumber!

Now simply press the Riser button in Calculation Panel, Project tab, for making the design.

Plumbing Riser Design Results

The result of greatest significance in the design is to obtain the necessary pressure in the Riser source node, which is shown in the Attended Water Networks Table:

Results-in-Plumbing-Riser-Design

Note that the pressure is calculated from the most unfavorable Water Supply Network which, in this case, corresponds to the highest elevation (Level 4) attended. The pressure required at this point is exactly equal to the pressure calculated by Plumber in the Nodes and Pipes tab for that Water Supply Network.

In the Diameters Table, will see the fixture units as well as probable flows and calculated and nominal diameters selected according to the specifications in the Project’s Diameters Manager:

Results-for-Plumbing-Riser-Pipes

For Plumbing Riser probable flow Calculation, Total Fixture Units values from Fixtures Manager table are used.

In previous table are also presented Final Flow Velocities in each pipe branch so that the user makes sure of the fulfillment of the permissible design velocities ranges.

In the Plumbing Riser table, warning icons will be shown when conditions such as occur: non-observance of maximum and minimum speeds (0.6 to 3 m / s), diameters which do not descend in the direction of flow, etc.