Metadata standards have risen specifically to solve the data management and interoperability issues in the large-scale digital transformation within buildings. Yet, the number of competing smart building metadata standards has caused a new set of challenges for the industry. These standards often have significant overlap in features but are not directly compatible, making it difficult for all building stakeholders to exchange data and application developers to be able to fully support building systems operation. However, over the past six months, two standards, the Brick Consortium and Real Estate Core Consortium (REC) have been working together on a major harmonization effort.
“Many of these standards started off with a particular vision, a particular scope and, over time, as the understanding of the problem evolves, you slowly creep into other domains. That’s what we have seen with Brick and REC. So, what we’re really trying to do with the harmonization is make clear semantic boundaries between the two, to remove the confusion of ‘when am I going to use this class or when you’re going to use this class’ when they seem very similar,” explains Gabriel Fierro of the Brick Consortium. “By eliminating these overlaps, and moving the standards to a point where they’re complementing each other in terms of the domains that they cover the concepts they model, rather than promoting competing concepts.”
Instead of continuing to compete, each consortium will take a role in a more complete building standard. Brick will take the lead on the equipment modelling side of the heavily combined standard, even migrating some of REC’s ICT concept classes over to Brick as part of the harmonization. REC, meanwhile, will take the lead on the location classes, with Brick relinquishing many of its location elements to allow REC to define them better. Other elements of the harmonization will see exchanges and redesignations of some roles and responsibilities but the majority of each semantic building standard will remain as they were before.
As well as clarifying how the classes and each of these ontologies relate to one another, it’s also important to understand how those classes, or instances of those classes, can be used inside the models themselves through associated sets of property changes. Properties are essentially just the relationships between the instances and the entities in each of these models. REC and Brick are now updating the semantics in each of these models to ensure that buildings can essentially use classes from Brick and REC together in a fixed set of broad relationships that are mostly used for building metadata models.
“It means that I can use Brick and REC together in my model of my building, without having to worry about some piece of software complaining that something needs to be a Brick location but it’s a REC location, meaning you did it wrong. All of that is now subsumed, which will also allow us to facilitate the migration of any existing models,” Fierro added during a recent webinar. “There’s a little bit of flexibility in how those properties are used with a clear path towards the harmonization. So, we can move past this world where everything is separate and towards one where we do have a unified collection of ontologies with clear semantic boundaries.”
Both Brick and REC are moving towards a full release of their harmonized standards. Brick is set to release its version 1.3 later this month but this will not apply the REC harmonization elements due to a their approval’s process. However, version 1.31 or version 1.4 by next year is expected to expand the class hierarchy of concepts, looking at integrating security and safety subsystems, as well as arriving at a decent model for heat pumps and chillers. “Every time we dig into this, it turns out there is just more variation and more properties that people want to know,” commented Fierro. REC, meanwhile, has released a preview of its upcoming version 4.0 which will be harmonized with Brick Schema.
“Initially, our plan was actually to do the full release around now, but we recognise that this has been a bit of a sort of skunkworks collaboration and over some time. So, it’s probably better for the broader community for us to release a preview version and have a number of months now to elicit feedback and see what may need to be adapted before a final release later this fall,” said Karl Hammar of the REC consortium, during the in-depth combined Brick-REC webinar. “So, that’s a long-winded way of saying that we don’t actually have an established feature roadmap post 4.0, because we’ve been so focused on [the Brick harmonization] in version 4.0.”
The harmonization of Brick and REC is a hugely significant step for open smart building data standards. While metadata standards began to solve the problem of data management in buildings, the competition between these ontologies created a new form of fragmentation in the market. Brick and REC are now pioneering this cooperation that could be a catalyst to the digital transformation of the real estate and smart building industry. There is also a DoE funded project to harmonize Brick with another leading standard, Project Haystack, which would further drive this open evolution.
“The Brick Schema and RealEstateCore combine the best of two worlds. We have created a complete open-source standard based on semantic web technologies which the industry can use efficiently for a long time,” reads a joint statement by Gabriel Fierro (Brick Consortium) and Erik Wallin (RealEstateCore Consortium). “We enable buildings to become good inhabitants of smart cities and contribute to reducing carbon emissions.”