BIM: What You Might Be Too Embarrassed to Ask Now — A Thorough Guide to the Digital Technology Transforming the Construction Industry

The term “BIM” has become increasingly common in the construction industry in recent years. You might feel it’s too late to ask, or you may not really understand what it actually means. This article thoroughly explains what BIM is, its basics, the transformations it brings to the construction industry, and the benefits and challenges of adopting it. Let’s look together at how digital technology is changing construction sites.

What is BIM?

BIM stands for Building Information Modeling, a method and concept for centrally managing all information about a building as a three-dimensional digital model. Simply put, it creates a virtual model of a building on a computer and links and manages all kinds of data—design drawings, construction information, component specifications, schedules, costs, and more—within that model.

Whereas traditional CAD handles drawing data such as plan views and elevations, BIM uses objects such as columns, walls, windows, and equipment as the unit of data. For example, when you place a wall in BIM software, that wall is assigned attribute information like height, thickness, material, and finish. Multiple objects are combined to build a complete 3D model of the building, from which plan views, sections, finish schedules, quantity lists, and so on can be automatically generated. In this way, a BIM model is not just a 3D drawing but can be considered a “database of the building.”

Why BIM Is Getting Attention

Why is BIM attracting so much attention now? The background includes structural issues in the construction industry and the wave of digitalization.

Japan’s construction industry has long been said to suffer from stagnating productivity. While labor shortages and the aging of skilled workers continue, many tasks such as drawing production and site management have relied on conventional manual processes. In other industries—especially manufacturing—3D CAD and digital data use have become commonplace, but the construction sector has remained dominated by paper drawings and 2D CAD, delaying digitalization.

BIM is expected to be a means to overcome these circumstances. The Ministry of Land, Infrastructure, Transport and Tourism launched the “i-Construction” initiative in 2016 to promote innovation in construction processes through ICT, and one pillar of that initiative is the promotion of BIM. Recently, with the digitization and electronic submission of building permit applications, a trend is emerging in which BIM use is becoming effectively mandatory. For example, from fiscal 2025, BIM-based permit applications will be introduced in stages, and from 2026 onward, plan reviews using BIM data are scheduled to become full-scale. It is expected that most future construction projects will use BIM, and the industry places importance on not falling behind this wave.

Benefits and Effects of BIM

What specific benefits does BIM implementation offer? Below are the main effects.

• Reduction of design errors and rework: Because the entire building can be examined three-dimensionally in a BIM model, clash checks can be performed early to detect drawing inconsistencies and component collisions. This greatly reduces rework and construction mistakes once the project enters the construction phase.

• Improved productivity and cost management: Automation of drawing production and automatic aggregation of component quantities improve the work efficiency of designers and construction managers. Accurate quantity information also enhances the accuracy of material cost and schedule estimates, contributing to better cost management.

• Smooth information sharing among stakeholders: Through the common platform of a BIM model, all project stakeholders—owners, designers, contractors, and equipment vendors—can always share the latest information. Misreading drawings and misunderstandings are reduced, improving communication losses. 3D visual information is also useful for explaining to owners and reaching agreements.

• Advanced construction planning and schedule management: BIM enables 4D simulation (construction simulation with a time axis) to reproduce construction procedures and schedules in virtual space. This allows detailed planning of crane and heavy equipment placement, material delivery routes, and worker safety, leading to shorter construction periods and improved safety.

• Use in maintenance and facility management (FM): BIM data remains valuable after handover. As-built BIM models can be used as a digital ledger for equipment management or referenced as current drawings during renovations. Information can be carried through the building life cycle, and in the future, advanced maintenance using digital twins based on BIM data will be possible.

Thus, BIM is a technology that offers multifaceted benefits across design, construction, and maintenance stages.

Differences Between BIM and Traditional CAD

To deepen understanding of BIM, let’s look at how it differs from traditional CAD. The biggest point is the granularity and consistency of the information handled.

With traditional 2D CAD, multiple drawings such as plans and elevations had to be created separately and manually reconciled. For example, if a column position changed, all related drawings had to be updated, and missed updates could lead to mistakes. Also, CAD drawings themselves did not include information such as quantities or specifications, so separate takeoffs or specification documents were necessary.

By contrast, as mentioned above, BIM consolidates all information in a single 3D model. Moving a wall or column automatically updates all related drawings, preventing missed changes. Each object can carry attribute data such as material, dimensions, manufacturer part numbers, weight, and price as needed. In other words, a single BIM model can simultaneously serve as design documentation, an estimate, and a parts list. Because information is centrally managed, changes are instantly reflected across related information, maintaining a “single source of truth” for the whole project.

In short, if CAD is a “drawing creation tool using lines and surfaces,” BIM can be described as a “building data platform using objects and information.”

Transformations BIM Brings to the Construction Industry

BIM implementation is expected not only to improve efficiency on individual projects but also to transform ways of working and business models across the construction industry.

First is a productivity revolution. BIM streamlines tasks that used to take enormous time, such as drawing coordination and quantity takeoffs, enabling smaller teams to deliver high-quality results despite labor shortages. This is an important measure to address the chronic shortage of craftsmen and engineers. Cost reductions from reduced rework also strengthen competitiveness in bidding.

Next is deeper collaboration. A shared BIM platform enables designers and constructors to work closely from early stages through “front-loading,” promoting collaboration that crosses the traditional boundaries of design and construction. The result is improved quality, reduced risk, higher client satisfaction, and fewer claims.

Furthermore, BIM promotes the creation of new services through digitalization of construction processes. For example, sharing BIM models in the cloud enables remote monitoring of site progress, or combining BIM with VR technology enables virtual experiences of expected completions—adding digital value. In prefab and modular construction, factory production based on BIM data is increasing, reducing on-site work. These trends accelerate DX (digital transformation) across the construction industry.

Current Status and Trends of BIM in Japan

Although BIM adoption in Japan lagged behind other countries, activity has accelerated recently. Major general contractors and architectural firms are already running BIM projects, and the use of BIM/CIM in public works ordered by the Ministry is expanding.

At the national level, as noted earlier, a major goal is BIM-compatible building permit applications. From fiscal 2025, electronic applications using BIM will be piloted in some cases; in spring 2026, plan reviews using BIM-created data will begin; and by 2029, nationwide application and review using BIM data are planned. In other words, within a few years, building permitting procedures are likely to shift to a BIM premise, and the industry must respond promptly.

Currently, it is said that just under 50% of companies and projects in Japan are “using BIM in some form.” Surveys in countries like the UK show over 70% of practitioners already using BIM, highlighting Japan’s lag. To close this gap, government and industry organizations are investing in training, guidelines, and adoption support. Especially important is spreading BIM to small and mid-sized construction companies and design firms; initiatives such as cloud-based affordable BIM software and simplified BIM tools are lowering barriers to entry.

Thus, BIM adoption in Japan is truly in a transitional phase. Companies that gain experience early and build know-how will increase competitiveness, while those that delay may risk losing business. Going forward, BIM response will be indispensable for survival.

Challenges and Key Points for BIM Implementation

Although BIM offers many benefits, there are several challenges to its implementation. Understanding these new-technology hurdles and taking countermeasures is key to success.

• Initial investment and costs: Initial adoption requires certain expenses such as dedicated BIM software licenses and high-performance PCs. Beyond software, employee training and developing operational rules also require time and cost. The point is whether these can be accepted as investments toward future benefits.

• Human resource development and learning curve: Operating BIM software and designing in 3D require familiarization. After adoption, some tasks may take longer than traditional workflows for a while. However, once in-house BIM talent is developed through initial trial and error, significant efficiency gains follow. Planned human resource development—such as sending younger employees to external seminars and training—is important.

• Workflow reorganization: BIM adoption is not simply a tool replacement but involves reforming business processes. Information-sharing procedures between design and construction and consensus-building processes with clients may need review. Establishing common rules (naming conventions, model creation methods, etc.) internally and coordinating with external stakeholders is required.

• Data interoperability with other companies: Projects involve multiple companies, so sharing and compatibility of BIM data is a challenge. Different software may not allow direct exchange of native data, but using neutral data exchange standards such as IFC format can address this. There are growing cases where the client prepares a platform and builds a common data environment (CDE) accessible to all stakeholders.

To address these challenges, it is effective to trial BIM operations on small projects or in specific tasks to build success cases. With management support and site cooperation, phased and planned adoption can reduce risk and foster establishment.

Simple Surveying in the BIM Era: An Easy Start to Site Digitalization

To maximize BIM’s benefits, how accurately and efficiently site information is digitized is crucial. For example, in renovation and remodeling, surveying existing buildings with laser scanners to obtain point cloud data for BIM modeling has become common. In civil engineering, aerial surveys using drones and 3D scanning to create terrain models for CIM (Construction Information Modeling) foundation data are increasingly used.

Previously, such 3D surveying required expensive equipment and specialized skills, but lately solutions that enable easy on-site digital data acquisition have appeared. One such approach is simple surveying using smartphones.

For example, there is a device called [LRTK Phone](https://www.lrtk.lefixea.com/lrtk-phone) that attaches a small RTK-GNSS receiver to an iPhone or iPad to achieve high-precision positioning. Using this system, a smartphone can quickly become a surveying instrument with centimeter-level accuracy (half-inch accuracy), allowing a single person to easily measure position coordinates and elevations. The coordinates of measured points can be plotted and managed on a cloud-based map, and combined with the smartphone’s built-in camera or LiDAR scanner to record site photos and simple point clouds. Tasks that once required specialized surveying teams and costly equipment can now be done with pocket-sized tools.

By using such simple surveying technologies, you can obtain accurate site data at low cost, making BIM preparation and digitalization of small projects much more accessible. For example, even for a small renovation, you can quickly capture as-built dimensions with tools like LRTK and create a BIM model from that data to proceed with planning efficiently. As a bridge between BIM and the site, skillful use of the latest surveying gadgets will be a key to construction DX going forward.

Conclusion: Shaping the Future of Construction with Digital Technology

BIM is not simply a trendy IT tool but a technology capable of fundamentally transforming how construction projects are carried out. By centrally managing drawings and information, productivity can be dramatically increased, and all stakeholders can make data-driven decisions. For an industry facing issues such as an aging population and work-style reform, BIM use is an unavoidable future.

However, to reap the benefits of digitalization, linking real-world sites and data is also essential. If you have not yet taken the step into BIM, start by adopting digital technologies in ways that are easy to try. Even collecting site data through simple smartphone surveying can let you experience the difference from traditional methods. That can be the first step toward BIM use and, ultimately, contribute to productivity improvements across the construction industry. Embrace digital technology and let’s shape the future of construction together.