Designing technological solutions in Autodesk Revit
Completion of the “Technological Solutions” (TS) section is especially important for facilities with state support and facilities where technological solutions are a key section. These are kindergartens, schools, office buildings, public service enterprises, parking lots, catering establishments, sports facilities, production facilities and many others – in general, everything except linear facilities and housing.
When developing these objects, it is the technological solutions that perform the main calculations of the building's filling, create the technical specifications, form the specifications of the recommended equipment and transfer the tasks for connection to the engineering systems to all related disciplines. Poor transfer of tasks and calculations from the technological solutions section leads to further errors in many sections.
Most companies design the section in AutoCAD or similar software, generate specifications in Excel and transfer tasks for related disciplines in separate files. Information modeling (BIM) is used by only a few. I believe that when developing the “Technological Solutions” (TS) section, it is also necessary to use information modeling technology. I will explain why further.
Dynamism of families in technological solutions
The “dynamics” of families is understood as the average required number of instance parameters that affect the change in the geometry of the element. Simply put, the more instance parameters and fewer sizes in families, the higher the dynamism. Different design disciplines use different degrees of “dynamics” of families. This is due to the specifics of the section. Here are some examples:
Architectural solutions. There is little “dynamics” in families, but it is still present in custom families such as windows and doors.
Design solutionsLarge reinforced concrete elements change geometry through instance parameters, that is, the “dynamism” is high.
Engineering solutions. Greater “dynamism” associated not only with geometry. In engineering solutions, it is also common to use selection tables to form sometimes up to several thousand variants of a family.
When developing BIM technology and families for technological solutions, we can, of course, change elements through instance parameters, achieving greater “dynamics”. But we should also take into account the customer's requests and think about the feasibility. As a rule, the requirements for the technological solutions section are the same for similar objects.
That is, if we design one state kindergarten, then the requirements for filling with equipment, furniture and other mandatory things will be similar in the second one. And since the filling is the same, then we should not go into the “dynamism” of families – it is better to provide the user with several already filled standard sizes.
Knowing this, we can simplify the user's work on marking, naming, numbering for the specification, which, of course, we will also output in Revit. In addition, usually the same furniture sizes are used in small quantities in TX projects – 2-5 pieces. That is, families with a large number of sizes are not expected.
Thus, for technological solutions we come to the use of family sizes, and not instance parameters or selection tables. For new equipment, furniture, plumbing, we will use our own size in the family, which will already contain all the necessary information for the specification.
Immediately after modeling all family instances, we will have an almost ready specification. Thus, we will significantly save time on forming the specification.
Sharing tasks in Revit
The created families can have ready-made filling with parameters and their values for reading. In the templates of models of technological solutions (TX), specially prepared views with tasks for all systems are formed – from power supply to communication. The main information on these views appears immediately after placing the elements in the model, and the TX engineer only needs to design the view.
An engineer of a related discipline loads the TH model as a link into his model and enables its display in a previously prepared form for incoming tasks. After that, he can see all the necessary data with the task from TH, and also click on any element of the linked model and get information on the necessary connection characteristics and energy resource consumption.
Automatic detection of model elements belonging to rooms and spaces
Autodesk Revit has a magical feature related to spaces. It allows you to read and filter all elements by their belonging to spaces. That is, you can get a list of elements that are in the “body” of a specific space.
There are many opportunities for technological solutions. For example, the designer can check the number of elements and spaces in the prepared specification. If some elements do not belong to any space, then there is an obvious error that needs to be corrected. It is possible to visually check the required and actual number of elements of technological solutions in a single space.
For example, a technologist knows that when designing a school, according to the instruction from the Department of Education, there should be 25 desks in each classroom. If the specification indicates more, then the model must be checked for errors.
Also, when designing large parking lots, the technologist is faced with the need to use the correct number of parking spaces of different classes in different fire compartments and on different floors. It is quite easy to make a mistake here, but verification specifications make this task easier and prevent inaccuracies.
Automatic creation of any specifications
Customers can change the requirements for the design of drawings and specifications. You can add and change specifications in Excel, but it is too long and complicated. It is more convenient and faster to keep everything in one program, especially since using specifications in Revit, it is easy to get information on almost any requirements without additional automation.
For example, on one of the projects we had to create specifications for parking lots, which indicated the numbers and classes of parking spaces, their affiliation with fire compartments, as well as their quantity for the parking lot as a whole and for individual compartments.
We met this requirement quite quickly, and now these specifications are created automatically on all projects.
Modeling and design templates
When designing in AutoCAD, the appearance of elements and the sheet depends on the preferences of users. The elements are the same, but each person sets up layers, sizes, text styles, and legend design differently. And often some legends and mandatory elements on the sheet are completely forgotten.
In Revit, it is much more difficult to make individual design. If a library of families and their standard sizes is formed, and a specialist designs based on a template, then all families on sheets and views are displayed the same, the same marks are used for model elements and families for notes.
Legends for templates are pre-formatted – the user inserts them without changing the content.
As a result, our TX projects are template-based, so it is much easier to obtain information from them. The design of the drawings is uniform and meets the company's requirements.
Always up-to-date data from architectural solutions
In interdisciplinary BIM, architectural and technological solutions are linked. In AutoCAD, it is impossible to always have up-to-date architectural plans. The architect must unload plans from AutoCAD so that technologists can use them as underlays. At the same time, the unloaded plan contains many unnecessary elements of the model and design, so the engineer-technologist needs to hide some layers, which does not always work as expected.
And if the architects changed something in the model and forgot to update the TX-base, then in different sections of the project we get different planning solutions, and this is already very bad. With Revit, you can make a two-way connection between technological and architectural solutions. Technologists can see up-to-date information from the linked model at any time, and architects can always see the up-to-date task from technologists.
Revit's standard feature for creating spaces in a linked model allows technologists to quickly populate the model with spaces with room names and numbers. If architects change something in the rooms, the information from the linked model can be easily updated.
But the main magic we see is when technologists use linked models to create and designed views. In Revit, you can display them “by linked view”. That is, the designed view from the architectural solution is copied to the view of the current TX model. In AutoCAD underlays, technologists design the view themselves, and in Revit we use the already designed AP view and then hide everything unnecessary. For example, technologists no longer need to create dimensions between axes according to GOST – the architects have already done it for them.
It is considered good form to create views in the AR model specifically for engineering equipment and networks. They are formed quickly from ready-made designed AR views. If they exist, then technologists only need to perform minimal adjustments, and not create a view from scratch.
It takes less time to prepare the TX section, and the data between disciplines is always up-to-date.
Automation of modeling and testing
The Revit model is an information database, and only then a geometric model. I have given all the advantages above for the “bare” Revit without taking into account automation. But it is also important.
A drawing of a technological solution in AutoCAD is a set of lines, points, texts, flat geometric figures and dynamic blocks. This is weakly structured data, so there is a high probability of errors, and it is difficult to read them programmatically and associate them with a specific functionality or category.
In Revit everything is simpler. It contains a database of configured categories, families and their standard sizes. Information parameters and their values allow you to identify an element and carry out any process with it when creating automation
Here are just a few examples of simple automations that can be created for process models:
Automatic filling of positions and groups for specifications.
Checking for the presence of certain legends on sheets.
Checking that the required parameters have been filled in.
Automatic assignment of numbers for parking spaces and motorcycle spaces.
Checking the number of required elements in spaces.
Checking whether elements belong to spaces.
Automatic modeling of family instances according to space.
And these are just the simplest options. In fact, the possibilities of automation are simply limitless.
Automation of calculations
A significant part of the calculations can be done using special plugins.
Here are some examples:
Calculation of the category of premises according to explosion and fire hazard. The technologist fills the room in the model with flammable and explosive substances. After that, it is necessary to add the necessary data from SNiP and get the assignment of the space category automatically.
Calculation of the required air exchange for a parking lot. This requires data on the parking lot space, its filling with parking spaces, as well as on the fuel used by the vehicles.
Such automations are more difficult to implement and require the involvement of qualified programmers, but everything is possible.
How we plan to speed up work with Revit
Instead of conclusions, I would like to present our plans on how exactly we plan to save time using Revit:
Object “Kindergarten” for up to 250 pupils. Stage “Project documentation”.
In AutoCAD, a TX project takes approximately 21 working days, in Revit it is planned to take up to 7 working days.Object “Parking for 300 cars”. PD stage.
In AutoCAD it takes 10 working days, in Revit it is planned to take 3 days.
The specified deadlines are not a joke, they are based on my own experience, the experience of colleagues and process engineers who are already working in Revit on similar objects.
These deadlines include: issuing assignments to related specialists, modeling, design, specification according to the requirements of the state examination and writing an explanatory note.
Of course, a lot depends on the individual preferences and skills of the designers. Some work faster in AutoCAD, while others work best in Revit. But at the company level, taking into account BIM and other technologies used, I choose Revit.
Author: Alexander Parshenkov, BIM analyst at PIK-Digital
Dictionary
Families are the main content in Autodesk Revit, from which information models are assembled. More simply, these are the same “cubes” from which we build 3D models.
Dynamism is the average required number of parameters of an instance in a family that affect the change of geometry and information in an element.
Design disciplines are sections of design documentation required to form a complete working design for a building.
