Revit Families: An Effective Tool for MEP Engineers

Families – they are integral to just about everything in life. This is doubly true for Revit families in the world of MEP (mechanical, electrical and plumbing) engineering. The importance of Revit family creation, especially Revit MEP family creation, is paramount in Revit 3D modelling. So, what is Revit MEP family creation and how beneficial is it?

Since the Revit platform was created by Autodesk, perhaps the more relevant question is: What is Autodesk Revit MEP?

Revit MEP from Autodesk is a building information modelling (BIM) software created specifically for MEP engineers or other MEP professionals. The software enables modifications, additions and communication in intelligent models so that MEP systems, regardless of their complexity, can be precisely designed and documented in a relatively short time. An entire project can be represented as a single model created by Revit MEP and is typically stored in a single file. This way, any changes effected in one part of the model is automatically updated and modified in other parts of the model.

What are the key benefits of using Revit MEP?

Using Revit MEP within a BIM workflow increases productivity, streamlines design and documentation and speeds up project completion from the design stage to the construction stage while automatically updating changes across the model for every single change anywhere in the model. It does so with a range of tools and features designed to improve productivity, such as Building Performance Analysis, Autodesk 360 Integration, Construction Documentation, Pressure and Flow Calculations, Pressure Loss Reports, Parametric Components, etc.

Revit MEP also reduces risks and helps create high quality designs. It can be used to develop detailed BIM-ready product models with a high level of accuracy by an HVAC (heating, ventilation and air conditioning) manufacturing company, for example.

The engineering design process is streamlined with the use of a single model. The single model enables a more efficient communication of design intent before the start of construction. Building performance is improved this way, as project stakeholders can make more informed and precise decisions on design.

A thorough knowledge of creating ‘families’ and ‘types’ can positively influence the length of time it takes to create a model. Families consist of categories and sub-categories. Each category consists of individual families. For instance, consider the Sprinkler Category.

The category of Sprinkler can create several kinds of sprinklers. It is possible for families within this category to perform different functions and use different materials, which makes each of them a family ‘type’. Each family type has a graphical representation. When a specific family and individual family type is used to create a design component, it is known as an ‘instance’. Each instance has its own properties.

The parameters of an element can be changed without changing the parameters of the family type. Only the instance or element or component is affected by the change. When the parameters of the family type are changed, every instance of elements in the family type are changed.

The three main classifications of families are: system, loadable and in-place families.

System families are preinstalled families and create basic MEP elements, such as ducts and pipes. . System family settings include types for levels, grids and drawing sheets.

Loadable families are created elsewhere and then uploaded into the project. They are typically used to create MEP fixtures or other elements that be purchased, moved or fixed in and near a building. Revit MEP helps create and alter loadable families, as they are customisable. External RFA files are used to create them, and then they are loaded into the project. A loadable family with many types uses type catalogs to select a type of family. This family type can be identified and loaded into the project without loading all the family types. Specific kinds of loadable families are nested and shared families.

The third kind of families is the in-place family, which can be used to create customised elements. When a project requires a special individual element, in-place families are created with a specific geometry. The geometry of in-place families will then reference other project geometry and change itself based on the changes of the referenced geometry. Revit can create a family with a single-family type to create an in-place element.

During Revit MEP family creation, Revit 3D modelling can help analyse electrical systems, especially lighting, in a project, since a source of light has its own properties in a modelling setting. Nested families, which are families within other families, can be used to create families with multiple light sources. This is done using the host geometry of the main family. Various lighting fixtures can also be included.

Besides electrical components, Revit MEP family creation includes the creation of elements from other trades too. Some of the examples of Revit MEP family creation components, or elements, are as follows:

Revit Mechanical Family Creation

• HVAC components
• Pipes - valve, strainer and pipe hanger
• Duct hangers
• Air terminals

Revit Plumbing Family Creation

•          Pumps
•          Fixtures - urinals, wash basins, water closets
•          Valves
•          Devices - measuring devices, gauges
•          Fittings

Revit Electrical Family Creation

•          Transformers
•          Distribution boards
•          Switches and sockets
•          Fire alarm devices
•          Lighting fixtures

Revit HVAC Family Creation

•          Fan coil units
•          Air handling units
•          Fire dampers
•          Diffusers, grilles and registers
•          Fittings and valves

Revit Firefighting Family Creation

•          Sprinklers
•          Valves
•          Fittings
•          Fire extinguishers
•          Cabinets

Autodesk’s Revit is BIM software that includes MEP features and is commonly called Revit Bim, but Revit is not BIM. Revit has been created for BIM. The nice thing about BIM, well one of the nice things, is that the data that is stored in BIM throws up a few advantages for users of Revit Bim. Convenient scheduling, marketing that is exclusive, design changes that can be quickly communicated and implemented throughout a project and easy access for MEP designers are some of the advantages of using the information in BIM models.

It’s easy to see why Revit families and their creation are an effective tool for MEP engineers, but since sound technical knowledge is required to create object-based models in Revit Bim, many Western firms opt for offshore Revit modelling services when local talent is either challenging to find or too expensive to afford. Offshore modelling services developed with Revit family creation are increasingly found to be affordable, precise and delivered on time, making it the popular way to go.

Elements to Consider in 3D BIM Coordination

Why is 3D BIM coordination so crucial to building design?

There are several elements to consider in 3D BIM coordination, and one of the first places to start the process is with a 3D coordinated model. Integrating architectural, structural and MEP trades together into a coordinated 3D model is part of the 3D BIM (building information modelling) coordination process. The BIM process is an effective 3D modelling tool that helps generate precise, accurate 3D coordinated models during the design development of a construction project. With a fully coordinated BIM model, users can see just how the architectural, MEP and structural systems have been coordinated in a 3D environment, and making changes becomes easy.

The process of 3D BIM coordination involves recording, using and reviewing detailed data about a building’s physical functions. The information can also be used to prepare task schedules in 4D, calculate project costs and material take-offs and optimise the sustainability of the overall business design. One way of looking at BIM coordination is to think of it as being a grouping together of 3 distinct functions, namely:

• Actual physical construction (building)
• Coordination of detailed data (information)
• Coordination of an accurate 3D model (modelling)

or BIM.

What is interesting about BIM coordination is that it involves much more than just modelling. It includes data and construction management responsibilities and improves efficiency in terms of saving costs and time and enables more informed decision-making.

A useful function of 3D BIM coordinated models is that they are used to perform clash-detection processes. A 3D BIM coordinated model can help find any clashes, interferences or shortcomings between architectural, structural and MEP systems. One of the most popular software used for this process is Revit, which has advanced features to help merge the different disciplines of the model effectively, helping architects, structural engineers and MEP engineers.

Models can also be studied to determine complex space allocation and how the different MEP trades can fit into the available space. Each of the building’s deliverables involving data-related tasks can be easily and clearly identified, tracked and coordinated at any point or stage of the project’s life cycle. Building risers, plant rooms, prefabricated corridors and ceiling modules can also be coordinated using quality checks in the process of BIM coordination.

Management tasks, such as common data environment (CDE) information management processes, are performed to support data exchange and help both model and data integration and coordination. Also included as part of the 3D BIM coordination process are constructability reviews, clash detection reports, virtual/personal coordination meetings with consultants, construction/project managers, sub-contractors, architects and engineers.

There are several benefits to be gained from using 3D BIM coordination, such as:

• Reduced errors by the construction team and design team
• Streamlined workflows in accordance with global standards
• Reduction of construction material waste
• Savings on total costs and project time
• Improved technology and innovative ways to maximise project value

A significant part of 3D BIM coordination involves BIM services, specifically MEP BIM, architectural BIM and structural BIM processes. These BIM services combine data from individual architectural, structural and MEP drawings, using Revit and Navisworks, to help generate intelligent BIM models that feature the following functions and products:

• Coordination
• Fabrication
• Optimisation
• Installation
• MEP engineering
• MEP BIM coordination
• MEP shop drawings
• MEP 3D modelling
• Mechanical room modelling
• Builders work drawings
• As-built drafting
• Piping spool drawings
• MEP quantity take-offs

Since the MEP systems of any building is crucial, it’s critical to be aware of some of the detailed MEP BIM modelling and drafting services available. They include:

• Mechanical equipment modelling
• Diffuser and grill modelling
• Electrical lighting fixture drafting and modelling
• Layout modelling
• Plumbing layout modelling
• Sanitary fixture Revit modelling
• Walk-throughs of MEP/BIM models
• Revit MEP Families Parametric modelling

Common Elements to Consider  

The classification of 3D BIM coordination can be as follows:

MEP BIM

Electrical Systems

• Electrical site plans
• Electrical one-line diagrams (riser diagrams)
• Electrical schematics
• Solar panel detailing
• Electrical, power and lighting plans

Plumbing Systems

• Drafting services for domestic water plumbing
• Plumbing and drainage drafting services
• Location and coordination of pipe sleeve requirements
• Isometrics, riser diagrams, details, schematics and schedules
• Sleeve/Penetration Drawings

HVAC (Heating, Ventilation and Air Conditioning) Systems

• Equipment schedules
• Compressed air and medical gas system plan drawings
• Demolition and existing plan drawings
• Equipment piping sizing and design layout plan drawings
• HVAC system drafting
• Details, schematics, schedules, legends and control diagrams
• As-built drawings, equipment specifications, coordination drawings, shop drawings and addendums
• Mechanical equipment layouts, submittals and elevation drawings

Heating Systems

• Boilers
• Direct vents
• Space heaters
• Indoor coil systems
• Heat pumps
• Wall and floor furnaces
• Forced hot air/water
• Thermostats
• Natural gas heating
• Heat pumps – standard and ground source

Ventilation Systems

• Overhead units
• Ductless split systems
• Sheet metal ducts
• Humidifiers/Dehumidifiers
• Central air systems
• Window/rooftop unit systems
• Air cleaners and filters
• Cooling Systems
• Air conditioners
• Air handlers

Architectural BIM

Using the BIM methodology, architects can develop digital design simulations capable of managing the vast stores of information that is part of an architectural project. Besides the 3D characteristics of models, BIM can incorporate 4D (time) and 5D (costs) associated with a project. Stakeholders can access and manage data intelligently and several processes can be automated, such as programming, conceptual design, detailed design, analysis, documentation, manufacturing, construction logistics, operation, maintenance and renovation/demolition.

Libraries of architectural models are available online, providing elements that can easily be incorporated into a project, saving time. This way, data is loaded, the quality of work can be improved, and the amount of decision-making and modifications made can be reduced, lowering both time and costs. 

Importantly, these elements, with unique characteristics, can be parametrically related to other project elements, which means that any changes on one element will effect automatic changes to other elements that are connected to or dependent on the first element. Thus, architects can interact with clients, builders and engineers in a shared process.

Structural BIM

The methodology of structural BIM modelling enables design analysis and review of structural elements in a project to further improve the overall design process. Structural BIM services consist primarily of 3D modelling, detailing and drafting. The analysis of these services results in cost-effective design and improves the safety of the design. Building geometry, location and space data, building properties, building materials and resources are better understood with structural BIM services. Some of the major structural BIM services are the following:

• Structural analysis
• Structural design
• 3D modelling 
• Steel structure detailing
• Creation of 3D, 4D and 5D BIM services
• Extraction of structural components
• High-quality construction documents
• Clash detection and risk management
• Intelligent parametric library development
• Precise quantity take-offs and cost estimates

With the help of BIM services, design errors are reduced from the improved coordination and communication of decisions. Thus, the main benefits of BIM services include:

• Better communication
• Faster approvals
• Improved coordination
• Easy modifications of design 
• Reduced errors
• Reduced time to create drawings and revisions
• Improved performance analysis, evaluation
• Improved project efficiency 

There are many elements to consider in 3D BIM coordination, and there are many ways to utilise and optimise the benefits resulting from 3D BIM coordination. Typically, the processes of 3D BIM coordination require the expertise and experience of several stakeholders, sometimes separated by countries. Many Western construction firms opt to outsources these processes to countries further east, such as India, since they have large groups of technically qualified, experienced, English-speaking personnel who deliver these BIM services accurately, clash-free, on schedule and cost-effectively. Bringing together clash-free MEP, structural and architectural systems after careful consideration of its many elements, high-quality 3D BIM coordination services remain an essential part of modern construction.