BIM Design of Hygienic Domestic Water Systems: New Block E at Carlo Poma Hospital in Mantova, Italy

Water quality is essential when designing hospital water systems

Designing the domestic water systems for a new hospital building involves far more than sizing pipe networks. In healthcare facilities, domestic water distribution systems must be designed from the outset to minimise the risk of water stagnation, maintain appropriate temperatures, promote regular water turnover and support efficient operation and maintenance throughout the building’s lifecycle.

This was the challenge faced by Italian engineering company RPA s.r.l. in the design of New Block E at Carlo Poma Hospital in Mantova, Italy. The RPA team, led by Marco Galazzo, Mechanical Engineering Technical Manager and BIM Coordinator, was responsible for the design of the mechanical systems, structural engineering and construction safety coordination during the design phase, working alongside engineering company Poolmilano, which was responsible for the architectural and electrical design.

The key engineering challenge was clear: selecting a calculation method that best supported the hygienic requirements of the water system while integrating modelling, technical data and engineering calculations within a single workflow. To achieve this, RPA used MagiCAD for Revit, adopting DIN 1988-300 as the design standard for sizing the domestic water networks.

“With MagiCAD we were able to size the networks with a focus on water hygiene without leaving the Revit environment. We could apply standards other than the Italian ones, monitor the model in real time and achieve the level of accuracy needed to develop a hygienically designed domestic water system.”
Marco Galazzo, Mechanical Engineering Technical Manager and BIM Coordinator, RPA s.r.l.

Project overview: a multifunctional hospital building

New Block E at Carlo Poma Hospital brings together a wide range of healthcare functions within a single facility, including the emergency department, diagnostic imaging, intensive care and high-dependency units, the immunohematology and transfusion service, outpatient clinics, microbiology, toxicology and virology laboratories, BSL-2 and BSL-3 containment areas, a galenical laboratory, an anticancer drug preparation unit, immunochemistry, clinical chemistry, haematology and pathology laboratories. The building design also includes a rooftop helicopter landing facility.

The wide variety of functions required an accurate MEP model already at an early stage. The BIM workflow was based on Autodesk Revit 2024 and MagiCAD 2025 for design, Autodesk Navisworks Manage 2024 for BIM coordination and checking, and Autodesk Construction Cloud as the common data environment.

The project was comprised of nine BIM models, four of which were dedicated to the mechanical disciplines: HVAC, medical and technical gases, domestic water and piping systems, and external utility networks. The piping model covered domestic cold water, domestic hot water, hot water circulation, demineralised water for laboratories, non-potable rainwater for toilets, and cold water supplies for air handling unit humidifiers.

Choosing DIN 1988-300 as the sizing standard

Because Block E is a healthcare facility, RPA designed the domestic water system with a strong focus on water hygiene. Following the evolving Italian regulatory framework, the design addressed key factors such as material selection, water temperature, water circulation and pipe sections prone to stagnation from the very beginning of the design process.

Although the most common standard for domestic water system sizing in Italy is UNI 9182, RPA selected to use DIN 1988-300 for the project because its calculation methodology better supported the hygiene requirements. The standard enables designers to size hospital water networks in a way that promotes water circulation, reduces the volume of water contained within the system and provides precise control over flow rates, pressures and pressure losses.

The use of DIN 1988-300 was compliant with recognised engineering practice as the use of technical standards issued by standardisation bodies in other European Union Member States is permitted in Italy and UNI EN 806-2 recognises DIN 1988 as one of the accepted calculation methods.

DIN 1988-300 enabled the designers to work with occupancy-specific simultaneity curves, loading units, higher permissible flow velocities in terminal branches and improved utilisation of available residual pressure. Rather than focusing solely on flow rates, the calculation method is based on balancing the available pressure against pressure losses throughout the network.

This approach allowed RPA to employ a sizing methodology better aligned with design requirements while keeping all engineering calculations fully integrated within the BIM workflow using MagiCAD.

Applying the standard directly within the Revit model

In MagiCAD, calculation standards are used as design settings that govern the sizing and balancing of MEP systems modelled in Revit. Once a calculation standard has been selected, the software applies its engineering rules to flow rates, simultaneity curves, permitted flow velocities, pressure losses and balancing conditions using the data associated with the objects and systems in the BIM model.

For Block E of the hospital, RPA configured DIN 1988-300 in MagiCAD as the calculation method for the domestic water systems and linked it directly to the project’s design data. The team defined pipe series, materials, dimensions, fitting types and insulation specifications within the MagiCAD dataset and correct operating temperatures and pipe series were assigned to each system.

This enabled the BIM model to function not only as a geometric representation of the building, but also as an intelligent engineering model supporting hydraulic calculations. Material properties, fitting characteristics, connections and connection nodes all formed part of the sizing process. Where manufacturer data was available, MagiCAD also used the actual pressure loss coefficients of the selected products, allowing calculations to more accurately reflect the components specified in the design.

In this way, the selected engineering standard becomes an integral part of the BIM workflow rather than a separate verification performed after modelling. All calculation results are available directly within the model through MagiCAD’s sizing and balancing reports.

“Everything is carried out within MagiCAD without having to leave the Revit environment. This makes the design and calculation process much faster and allows us to verify the results directly in the BIM model.”
Marco Galazzo, Mechanical Engineering Technical Manager and BIM Coordinator, RPA s.r.l.

Connections and connection nodes for partially defined equipment

One of the project’s challenges was that some of the equipment and connection points, particularly in the laboratory areas, had not yet been fully defined in the architectural model.

MagiCAD enabled RPA to model system connections as MEP objects independent of the architectural model, assigning the correct design flow rate to each fixture. This meant that hydraulic calculations were not dependent on the level of detail available in the architectural objects.

The team used connection nodes for future connections and for equipment that had not yet been fully specified. This made it possible to assign the required flow rate and pressure at estimated connection points, ensuring that their demand was included in the hydraulic calculations even before the final equipment selection had been completed.

Sizing and balancing as continuous design verification

DIN 1988-300 sizing was used not only as a final verification step but also as a design tool throughout the modelling process. RPA carried out calculations on individual network sections and branches, continuously verifying pipe diameters, nominal and design flow rates, pressure losses and available pressure.

Domestic hot water circulation balancing also played a key role. In a hospital environment, circulation serves not only to ensure user comfort and the immediate availability of hot water but also to maintain stable distribution conditions throughout the system. MagiCAD enabled the team to verify flow rates, temperatures and the operating points of thermostatic balancing valves, while automatically highlighting any issues through its calculation reports.

“Another major strength of MagiCAD is its intelligent valve objects. They include complete operating curves and provide the actual operating points directly within the calculations.”
Marco Galazzo, Mechanical Engineering Technical Manager and BIM Coordinator, RPA s.r.l.

Monitoring dead legs and reducing the risk of water stagnation

Within RPA’s workflow, MagiCAD’s dead leg alerts became another valuable design verification tool. During the sizing process, the software automatically identified terminal pipe sections and future connection points where maximum allowable water volumes were exceeded.

This is particularly important when designing to high hygienic requirements, as infrequently used pipe sections or excessive water volumes can increase the risk of stagnation. Identifying these conditions directly within the BIM model enabled the design team to evaluate and resolve potential issues before progressing to later project stages.

Results of the BIM workflow with MagiCAD

Using MagiCAD within Revit enabled RPA to apply a carefully selected engineering standard directly within the BIM model, maintaining continuity between modelling, engineering data and design verification.

The workflow supported accurate network development, material management, temperature control, sizing according to DIN 1988-300, domestic hot water circulation balancing and continuous verification throughout the design process.

The result was a design process in which domestic water system design was not based on calculations performed separately from the BIM model, but instead became an integral part of the BIM workflow. For a hospital project, this provides greater control over the design decisions that influence water quality, water circulation, system water volume and the management of stagnation risks.

“MagiCAD allowed us to apply a calculation standard that differs from the one commonly used in Italy directly within the Revit model, while maintaining full control over flow rates, pressures, pipe sizing and balancing of the domestic water system. This proved particularly valuable in supporting a design approach focused on water hygiene.”
Marco Galazzo, Mechanical Engineering Technical Manager and BIM Coordinator, RPA s.r.l.

About RPA s.r.l.

RPA s.r.l. is an engineering consultancy headquartered in Perugia, Italy. Founded in 1969 as RPA Ricerche e Progetti, the company operates across a broad range of disciplines, including urban and regional planning, buildings, infrastructure, environmental engineering, hydraulics and transportation.

The company employs more than 50 professionals, including engineers, architects, geologists, environmental scientists and specialists across multiple engineering disciplines. Its BIM team includes professionals certified in accordance with UNI 11337-7, comprising one BIM Manager, three BIM Coordinators and eleven BIM Specialists.