How 3D Point Cloud Scanning Is Changing Exterior Design: Visualizing the Finished Image with LRTK

Exterior (landscaping and site work) refers to all areas around a detached house, such as the yard, driveway, gates and walls, approaches, tiled pavings, and privacy fences. In exterior design, it is necessary not only to consider aesthetics and functionality but also to accurately grasp even slight deviations and elevation differences on the site when planning. For example, differences of a few centimeters in slope or dimensional errors can lead to problems such as poor rainwater drainage or gated fences not closing properly. However, traditional manual measurements and reading drawings alone can miss subtle on-site differences and fail to fully convey the finished image to the client.

A new technology drawing attention for solving these issues is 3D point cloud scanning. Recently, using an easy, high-precision surveying system that leverages a smartphone—LRTK—you can obtain centimeter-accurate 3D data simply by walking the site, and use it for design and construction. This article explains the changes and benefits that 3D point cloud scanning with LRTK brings to exterior work. From accurately capturing current conditions to sharing finished images via CAD and AR, improving site management and construction accuracy, and the ease of smartphone surveying, let’s look at how the latest technology is transforming exterior design.

"Centimeter-level accuracy" required in exterior design

In exterior work, slight dimensional errors can have a major impact later on. Below are examples where centimeter-level accuracy is required:

• Drainage slope: If the slope of an approach or driveway is off by a few centimeters, rainwater may not flow properly and puddles can form.

• Fence and gate positions: If fence post locations or gate widths are slightly off, doors may not close properly or gaps may appear, causing functional and aesthetic problems.

• Flatness of tiled paving: If tiles on an entrance approach differ by even a few millimeters in height, they can cause tripping hazards or detract from the finish quality.

• Boundaries with neighboring properties: Walls or privacy fences along property lines must be installed based on accurate site dimensions; otherwise, issues such as encroachment or gaps can occur.

• Interfaces with existing structures: If the positions of building foundations, existing garden stones, or piping are not accurately known, newly designed decks or flower beds may interfere with them.

As shown, exterior design requires millimeter- to centimeter-level accuracy, but measurements using traditional tape measures and spirit levels made it difficult to completely prevent small errors. Paper drawings alone often fail to convey vertical information adequately, leading to on-site misunderstandings like “this isn’t what we discussed.” That’s where digital condition capture via 3D point cloud scanning comes in.

Smartphone-based 3D point cloud surveying: what is LRTK?

The recently introduced LRTK (smartphone RTK surveying system) enables anyone to perform high-precision surveying easily without complex equipment. LRTK is a technology that turns a smartphone or tablet into a versatile surveying device with centimeter-level accuracy by attaching a compact RTK-GNSS receiver to the device. RTK-GNSS is a method that corrects satellite positioning information to achieve high precision; traditionally, specialized equipment was required, but with LRTK you can measure positions with global coordinates using just a smartphone.

A major feature of LRTK is 3D point cloud scanning. By simply holding up your smartphone camera and walking the site, you can capture point cloud data that records the surrounding environment in three dimensions. 3D measurement that once required expensive laser scanners can now be performed with a smartphone combined with an LRTK device. The achievable accuracy is about horizontal ±1–2 cm and vertical ±3 cm, comparable to professional surveying instruments. Yet the equipment is pocket-sized and lightweight, designed to be easy to carry and use on site.

LRTK is easy to handle even for those without special training, allowing one person to complete surveying quickly. Positioning and point cloud capture are done by pressing a button in the app, and data is recorded automatically. Captured data can be reviewed on the smartphone immediately and shared with office colleagues via the cloud. This combination of ease of use and practical accuracy significantly lowers the barriers to introducing it into exterior work.

Don’t miss on-site deviations or elevation differences: benefits of accurate site capture

When planning exterior renovations or site work, the first priority is to accurately understand the current conditions (the state of the site and structures). By using LRTK point cloud scanning, you can obtain detailed data down to the smallest areas of the site and not overlook slight deviations between the drawing and the actual site.

For example, in older houses the building’s position or height may differ subtly from the original plans. Traditionally, key points were measured with tape measures or laser distance meters, but the limited number of measured points risks missing areas that cause errors. With LRTK point cloud data, walls and site shapes are captured by millions of points, making it possible to accurately determine building tilt or distances from boundary lines.

Moreover, the accuracy of capturing ground elevation differences improves dramatically. Previously, people measured heights at multiple points with levels or water levels and inferred contour lines, but point cloud scanning captures the site’s undulations as a surface, allowing slopes and steps to be understood intuitively. This makes it possible to plan drainage, stairs, and ramps based on actual conditions.

In addition, dimensions of existing structures like buildings and walls can be obtained accurately. Detail measurements that affect design—such as the width of an entrance porch or the spacing between carport columns—can be measured directly on the point cloud data. There’s no worry about discovering unmeasured areas later; with a single scan you can obtain a “digital copy of the site.”

By accurately capturing the current conditions with LRTK point cloud scanning, the foundation for planning is firmly established at an early stage. Designers can concentrate on planning with confidence, greatly reducing the risk of later having to redo work because “the site differs from the drawings.”

Deploying 3D point cloud data to CAD and AR: sharing the finished image

High-precision point cloud data obtained with LRTK can be highly useful in subsequent design and proposal processes. Basing work on current-condition data makes visualizing the finished image dramatically easier.

Workflow for using 3D point cloud data in exterior design:

• On-site 3D scan – Use LRTK to convert the current conditions into point cloud data. The site and building details are digitally recorded.

• Incorporation into design – Import the point cloud into CAD software or exterior-design-specific software to create plans that reflect the site. By referencing the point cloud while adjusting layouts and dimensions, you can resolve clashes and inconsistencies during the design phase.

• 3D visualization of the finished image – Generate 3D renderings (perspectives) from the created plans. By combining building models generated from the point cloud with newly designed exterior structures, you can realistically depict the post-construction appearance.

• Projecting with AR on site – Using LRTK’s AR features, you can overlay the 3D finished model onto the actual site. Viewed through a tablet, a virtual yard or gate appears in the pre-construction space, giving the experience of standing in the completed site.

For example, when adding a wood deck and flower beds to a sloped garden, first scan the entire garden and the building exterior with LRTK. Designing the deck’s shape and height based on that point cloud allows you to plan a layout that fits the house foundation and window positions precisely. Displaying the 3D model in AR at the site lets the client see a virtual wood deck installed in their garden. Since the finished image that’s hard to convey with drawings alone can be shared, the persuasive power of design proposals is greatly increased.

Using data consistently from site to handover

Accurate point cloud data and AR technology obtained with LRTK can be used in every stage of exterior work. From surveying and design to client presentations, construction, and as-built management, consistent data sharing enables smooth progress.

• Streamlined site surveys: Previously, staff often visited sites multiple times to take detailed measurements and photos. With LRTK, you can capture point clouds and geotagged photos in a single visit and bring nearly the entire site back digitally. If questions arise later, they can be checked in the data, greatly reducing the need for additional measurements or re-surveys.

• Clear explanations to clients: As mentioned above, showing a 3D model generated from point clouds in AR allows clients to intuitively understand the finished image. Presenting it on a tablet during meetings lets you visually demonstrate things like “a wall of this height will be here” or “this is how it will look with a parked car,” making it easier for clients to understand and accept the proposal.

• Information sharing with craftsmen and subcontractors: Craftsmen responsible for the site can also use point cloud data and AR for information sharing. For example, before construction they can compare the site point cloud to the design drawings to check details, or use AR to verify layout positions while marking out. Slope and height information that is hard to convey by word or 2D drawings is shared through data, preventing construction errors caused by differences in workers’ mental images.

• As-built management and records: After completion, you can scan the site again with LRTK to keep 3D data of the as-built condition. Comparing it with design data makes it possible to verify finishing accuracy and quickly correct any slight deviations. These data can be stored as records and prove useful for later renovations or maintenance. Digitally archiving the history of exterior work can raise a company’s level of construction quality management.

Quantitative improvements brought by LRTK adoption

Introducing LRTK into exterior work can bring the following measurable improvements:

• Improved surveying and design accuracy: Current-condition measurement accuracy improves dramatically. While typical GPS is said to have errors of about 5–10 m, LRTK achieves an error range of ± a few centimeters. Where manual measurement often yields vertical errors, LRTK can capture vertical information within about 3 cm. Designing based on accurate data reduces post-construction deviations and rework.

• Greatly shortened work time: Point cloud scanning captures a vast number of measurement points at once, so surveying work that used to take hours can be completed in minutes. For example, even a 100 m² garden can be scanned in detail by one person walking around for just a few minutes. As a result, the number of site visits is reduced and the overall design period shortens.

• Improved information sharing: Since point clouds and measurement data can be shared via the cloud, communication between site and office and within construction teams is faster. Colleagues in remote locations can immediately view the data and discuss it. The need to send drawings by email or explain situations verbally is reduced, improving the team’s overall communication efficiency.

• Enhanced record-keeping and traceability: Point cloud data and geotagged photos can be stored as digital records and reviewed chronologically. If you save 3D data before and after construction, you can later verify questions such as “what was the ground condition before construction?” or “is the finished height as planned?” Keeping evidence of exterior work in data and numbers increases external trust.

• Improved construction accuracy and quality: The gap between design and site narrows, making it easier for craftsmen to work at accurate positions and heights. Visual support via AR and accurate guidance for stake positions minimize finishing deviations. As a result, rework and remedial work decrease, contributing to fewer quality-related complaints and lower warranty costs.

The ease and cost performance of smartphone surveying

Hearing about advanced technology may make you think “isn’t it hard to introduce?” but LRTK offers ease of use and cost performance that even small- and medium-sized exterior contractors can readily adopt. The biggest attraction is that all you need is a smartphone to start high-precision surveying—no need to acquire specialized equipment or hire surveyors.

First, the operation is intuitive and simple. Attach a dedicated device to your smartphone, press the app’s “start surveying” button, and walk—the simplicity means it can be used without special skills. There’s no need to spend a lot of time on training; you can start using it on site the same day you introduce it.

Second, the cost efficiency is far better than before. Conducting wide-area 3D surveys once required expensive laser scanner equipment or outsourcing costs, but LRTK has dramatically lowered that hurdle. With a relatively small budget you can equip your company with surveying tools, so the return on investment is high. Savings on labor and outsourcing, along with reduced rework costs from fewer mistakes, offer indirect economic benefits.

Furthermore, because everything is handled with a smartphone and a small device, transporting equipment to the site is easy. Bulky tripods and cables are minimized, and you can survey light and solo even in narrow lots or distant sites. The convenience of carrying “one device per person” in your pocket and quickly taking it out when needed is a strength not found in conventional surveying equipment.

If you want to differentiate your exterior design from competitors, start with smartphone surveying. In fact, LRTK is already being adopted in civil engineering and building construction sites, and its convenience is attracting attention. In the exterior field as well, it could become the standard technology of the future. 3D point cloud scanning and AR using LRTK are trump cards that dramatically enhance accuracy and proposal power. Why not harness the latest technology to gain clients’ trust while improving work efficiency?

With 3D scanning and AR on your side, step up to the next stage of exterior design.