Modeling Plumbing Systems

BIM for Architecture, Engineering, and Construction Curriculum


Placing Plumbing Fixtures in the Architectural Model

What are the required clearances for restroom fixtures per your applicable building code?

The requirements vary per the local building code. The requirements per the Uniform Building Code include, for example:

Toilets: 30" (0.76 m) -wide clearance side to side, 26" (0.66 m) clearance in front

Showers: Minimum 34" by 3\" (0.86 m) square

ADA requirements are more stringent still.

Toilets: 60" (1.52 m) -wide minimum clearance located 16" to 18" (0.40 m to 0.46 m) from the wall.

Sinks: A 30" (0.76 m) -minimum clearance floor space in front of lavatories that extend 17" (0.43 m) minimum from the wall.

What are the advantages and disadvantages of using wall-mounted plumbing fixtures versus floor-mounted?

Wall-mounted plumbing fixtures keep the floor area clear, allowing easier access when cleaning floors. The disadvantage is that space must be provided for the supply and sanitary piping in the wall behind the fixture. And the wall must be reinforced to carry the structural loads.

How does the mounting location affect the routing of the sanitary and water piping?

On the supply side, there is no difference. For sanitary piping, mounting location determines where space must be provided; for sanitary piping, either below the floor or in the wall behind the fixture.

Copying Shared Elements into a Plumbing Model

How can you control the types of fixtures copied during a batch copy?

You can select the fixture types to be batch copied within the Copy Monitor dialog box.

What are the advantages and disadvantages of mapping fixtures to new types?

In general it is better to copy the original types. The exception is if you have a plumbing fixture that is not MEP-friendly (does not have connectors and other MEP properties). 

Modeling Sanitary Systems

How are the horizontal branch pipes that run below a floor typically concealed?

If the pipes will not be covered by a ceiling, then a soffit can be provided to enclose and conceal them. 

Can you use multiple vertical risers to reduce the length of the branch pipes and the vertical clearance required to provide the minimum slope?

Yes, this is an effective strategy when vertical clearance is limited.

What are the biggest challenges when trying to find auto-routing solutions?

The biggest challenge is whether the required space is available to allow the connections (elbows, tees, and so forth) between the pipe sections to be made. If space is not available based on the settings specified, an auto-routing solution cannot be found.

Do the types and sizes of connector elements loaded in the project affect the auto-routing solutions available?

Yes, the auto-routing solutions will only have access to those elements loaded in the project. Loading more types and sizes of connectors can increase the number of solutions found.

If an auto-routing solution cannot be found, what strategies can you use to assist with finding an acceptable routing?

If an auto-routing solution cannot be found, you can manually place some of the major pipes and rely on auto-routing to determine layouts for specific smaller regions of your system.

Modeling Fire Protection Systems

What factors influence the design of a wet fire protection system?

The factors considered include: the usage of the space, the hazard classification of the building, the coverage area, the water flow, and the water pressure. 

What is a typical spacing between sprinklers?

The sprinkler spacing will depend on the flow rate required and the water pressure available. Typical spacing can range from 12' x 12' (3.6 m x 3.6 m) to 20' x 20' (6.1 m x 6.1 m). 

What factors need to be considered when determining the elevations of the main and branch pipes?

The biggest consideration is going to be the height of the ceiling plane, whether the sprinklers will be located on or below the ceiling, and the elevations of potential obstructions in the ceiling plane, such as ductwork or structural elements.