Will the computer say ‘please go ahead’?

Everyone wants accurate and efficient regulatory processes. How can we improve the regulatory process for buildings using BIM and Rules? 

The path to BIM-based Building Permitting

Currently the building permit process is based on skilled people preparing drawings and written forms and documents, followed by skilled people reviewing the submission against the legislation, regulations and central and local government guidance. The process is weakened by two problems: it may be slow and it may be inaccurate. The slowness makes the building permitting stage a huge risk for the applicant. The development of the design is put ‘on-hold’ and the teams may be distracted by other work. Meanwhile the checkers may focus on only the most clearly defined clauses relating to fire and structural safety, neglecting clauses where life-safety is not at stake and where detailed analysis may not be quick such as energy saving and carbon reduction. It has been reported that particular designers are known to make certain kinds of mistakes, but that many mistakes go undetected.

The implications of getting the ‘zoning’ and ‘technical’ building permit and any community approval vary in different countries: it may increase land-value, it may allow work on site to commence, it may start a sequence of on-site inspections. But the regulatory process is society’s most important opportunity to shape the built environment and the social, economic and environmental future.

Since the early 1990’s we have had an alternative to paper in the form of electronic drawings and documents, and an alternative to the postal service in the form of email and direct server connections. Many countries have taken the first step towards automation by accepting electronic application forms, payment, and PDF representations of the submission.

The next stage in improving on this basic approach has been to make the PDF or other format documents scalable. With a clear relationship between the document and the real world (1:20, 1;50 etc)  then requirements around size and areas can be measured and checked on-screen or on paper print out.

The next stage has been to share the 3D or BIM models as supplementary information, useful to give the understanding of the overall layout and the nature of the spaces being provided – even if the drawings and schedules that are the subject of the detailed examination are not derived from the 3D model.

Even before the 1990’s far-sighted people saw that the process of mentally interpreting designs into drawings and then mentally re-interpreting drawings into the design is error-prone and inefficient.

In the UK and elsewhere, computer tools have been developed that represent the building, not the drawing. For example in 1977 Edinburgh University working with a Scotting social housing provider were preparing housing estate plans in detailed 3D models that could be checked for energy efficiency, stairway usability, sufficient storage and habitable space.

The role of standards and openBIM

Automated code compliance checking depends on using a ‘rule-engine’ with access to three kinds of information:

  1. A digital representation of the regulation leading to a pass/unknown/fail decision. This representation must be able to represent the requirements, but also when the requirements is applicable or selected and when it is excepted .
  2. A dictionary of links between the language of the regulation and the language of the building representation.
  3. A building representation – which can be a BIM model but can also include information in the application forms, or it can even be a human user willing to answer questions about the building design

Unfortunately each of these three resources can come in a huge number of obscure and unreadable forms: different languages, proprietary formats, rule languages and so on. Luckily there has been a lot of work put into developing a common way of representing these three things. Electronic information has moved on from proprietary formats and low-level forms of imaging like scans. Under the flag of ‘openBIM’, standards have been developed that support open communication. These have been developed by the industry, by consensus and by voluntary effort.

The role of buildingSMART

buildingSMART[1] is the international not-for-profit organisation that has led the way in developing a suite of standards, headlined by the ‘IFC[2]’ (think of ‘Information for Construction’) and supported by the ‘bsDD[3]’ (think of ‘Data Dictionary’). IFC represents the ideas about the build environment and its regulation, it organises these ideas as a single comprehensive diagram and offers several ways of communicating this information between organisations. The ‘bsDD’ is the online dictionary of extensions and translations which supports the implementation of IFC in different contexts and countries. Almost all buildingSMART standards are based on ISO standards or become ISO[4]  and CEN[5] and national standards including SFS[6].

The Regulatory Domain and Information Requirements

buildingSMART develops standards through a network of country Chapters including in Finland[7] and working groups such the Regulatory Domain[8]. These two routes allows buildingSMART to consider the common needs across the globe but also to accommodate the specific needs of specific countries. The Regulatory Domain is developing “Guidance for regulators on ‘openBIM” as a document that will help government agencies to understand how ‘openBIM’ eliminates costs and risks and offers the opportunity for accurate and efficient services.

When thinking about regulation, it is especially important that designers and engineers should be able to describe their designs and that regulators are able to check these designs using generic software developed around the world, without being tied to a single application. The majority of the topics which are regulated are common across the globe, such as structural and fire safety, energy usage, accessibility and so on. These are influenced by a common set of things like slabs and columns, stairs and walls. Many attributes are common, such as materials, conductivity, widths and slopes. The buildingSMART Regulatory Domain is conducting the “Regulatory Information Requirements” project lead by Tomi Henttinen[9] from Finland. The Finnish RAVA3Pro project is working in close connection with the buildingSMART RIR project. The starting point is reviewing building regulations and guidelines from around the world to identify these common needs.

Since starting in earnest at the beginning of 2023, England, Scotland, Singapore, Estonia and Finland have contributed lists. These lists come from subject experts and from detailed analysis of the regulatory text. The editorial process is reviewing all the proposals. Some suggestions are really very specific to a nation or region. Some are better derived from the geometry and relationships in a BIM model. Some are cross-references to other clauses, diagrams or documents. Some are about the process, not the design. But there are still plenty that are generally useful and can be defined and documented at the international level. They will be added to the buildingSMART Data Dictionary, with translations into English, Finnish and other languages. This should encourage the development of common information requirements, and both information checking and rule-checking applications.

There is still room for local requirements such as reporting the ‘number of saunas’ and for the local regulations, which may combine international and local applicability and requirements in different ways. For example, what counts as a tall building or what counts as a corridor? Each country can combine the requirement metrics with different applicability’s, selections and particularly the exceptions. Napoleon called Britain ‘a nation of shop-keepers’ so it is not surprising that the UK energy regulations exempt shop-front windows!


Automated permit and code checking may be the biggest challenge for digital representations of buildings and regulations, particularly because there is no contract and little negotiation possible between the application and the inspectorate, and yet the outcome is so important to society. buildingSMART is promoting the use of open standards, which can make accurate and efficient solutions possible. 


Kirjoittaja on yksi avoimen tietomallintamisen yhteistyöverkosto buildingSMARTin johtajista, konsultti, tohtorikoulutettava Nicholas Nisbet (University College London).

Hän katsoo, että kaavoitus- ja rakennusvalvontaprosessi on yhteiskunnan paras mahdollisuus muokata rakennettua ympäristöä ja vaikuttaa tulevaisuuden sosiaalisiin, taloudellisiin ja ympäristöllisiin kysymyksiin.

Rakennuslupaprosessilla on ollut kaksi ongelmaa: se on hidas ja toisinaan myös epätarkka. Asiakirjoja tarkastettaessa saatetaan keskittyä palo- ja henkilöturvallisuuden kysymyksiin ja energiatalous ja vähähiilisyys voivat jäädä vähemmälle huomiolle.

Tietomallin käyttäminen luvan hakemisessa auttaa tässä. Tietomallista voidaan automaattisesti tarkastaa, että suunnitelma on määräysten mukainen. Tämä edellyttää, että suunnittelussa käytetty ohjelmisto ja tarkastettaessa käytettävä ohjelmisto puhuvat samaa ”kieltä”. Näin on asia silloin kun käytetään avointa tietomallia (openBIM). Avoin tietomalli saa hankkeen kunkin osapuolen käyttämät, eri tarkoituksiin kehitetyt tietojärjestelmät toimimaan yhdessä. Silloin eri käyttäjillä on mahdollisuus valita työhönsä erilaisia sovelluksia, ja sovellusten yhteistyö perustuu yhdessä sovittuihin prosesseihin, menetelmiin ja terminologiaan.

Kirjoittaja esittelee lisäksi lyhyesti kansainvälisen buildingSMART-yhteisön toimintaa ja organisaatiota.

Juhani Nortomaa

Nicholas Nisbet

Nicholas Nisbet has been developing Building Information Modelling and Automated Code Compliance since 1977. He is an international consultant and director at AEC3 and author of several ISO standards. He is a Fellow at buildingSMART and leads its Regulatory Domain. He is currently working on a PhD at UCL, London.

[1] buildingSMART

[2] IFC: Industry Foundation Classes

[3] bsDD: buildingSMART Data Dictionary based on ISO12006-3 

[4] ISO: International Standards Organisation

[5] CEN: Comité Européen de Normalisation

[6] SFS: Finish Standards Association

[7] buildingSMART Finland

[8] buildingSMART Regulatory Domain

[9] Tomi Henttinen Tomi Henttinen <>