Neda Ziaei, BIM Manager
If you’re planning to build in a spot with stunning harbour or coastal views, there’s a good chance the council will want to know how your project might impact the area’s visual character. In fact, in many sought-after locations around Sydney, submitting a Visual Impact Assessment is now a must-have for development approval.
That means you’ll need a Visual Impact Report, complete with photomontages that clearly show how your proposed build will sit in the landscape. These images aren’t just pretty mockups created by guesswork – they need to be accurate, technically sound, and certified by a Registered Land Surveyor to be legally compliant and accepted by council or stand up in court.
In this case study, we’ll walk you through how CMS Surveyors helped one client pull all of this together – from precision photomontages to a professional Visual Impact Report – and got them over the line with their Visual Impact Assessment.
| Client | Private Residential Client |
| Architect | SJB |
| Site | Military Road, Dover Heights, Sydney |
| Deliverables | Photomontage and Visual Impact Study to support a Visual Impact Assessment |
| Methodology | Traditional survey, Scan and Point Cloud, BIM (Revit), Photomontages |
| CMS Team | Neda Ziaei (BIM Manager), Chris Larmour (Registered Surveyor) |
Dover Heights Residential Client
Summary
When design meets coastline, views are everything. At this site in Dover Heights, a proposed residential development required careful calibration to ensure architectural ambition could co-exist with neighbouring sightlines and pass council review.
Under time pressure, access limitations, and the potential scrutiny of the Land and Environment Court, CMS delivered a fast-turnaround Visual Impact Report inclusing photomontages by using advanced point cloud data and photographic analysis. This Visual Impact Study assesses how the new development would impact the visual landscape, considering key viewpoints from neighbouring properties towards the ocean. The photomontages successfully illustrated that the minor design non-compliance would have no further impact on views.
Client request for photomontages to supprt a Visual Impact Assessment
A survey and Visual Impact Study including photomontages is required to support a Visual Impact Assessment, with particular attention to confirming that no line of sight exists between ground level and the first-floor features (such as windows) of the objecting properties.
The timeframe for the council’s review was limited, making it challenging, if not impossible, to coordinate access to all four properties and seven camera positions for the survey. Ideally, this would be completed in a single visit to ensure the efficiency and accuracy of the survey necessary for the Land and Environment Court photomontages.
Methodology
Surveying and Data Collection
CMS Surveyors leveraged expertise in coordinate systems, survey techniques, 3D modelling, and photography, in conducting this Visual Impact Study. The process began with the on-site collection of survey data and photographs, which were then tied to a precise coordinate system. To create the visualizations, a combination of the design model, point cloud data, and captured photographs was used.
Point Cloud Creation and Alignment
Using a laser scanner, the site and existing structures were surveyed, generating a point cloud consisting of millions of data points, effectively creating a 3D snapshot of the environment. This scan data was linked to the Australian Height Datum (AHD) and Map Grid of Australia (MGA), ensuring accurate geospatial alignment. The proposed building model was then positioned relative to the surveyed data, including all relevant physical features and site boundaries.
Camera Positioning for Photomontages
Photographs provided by a third-party were integrated into the study, with the camera positions and characteristic determined using the point cloud as a reference. Control points from the scan were applied in perspective matching software to precisely calculate the camera’s orientation, location, and lens settings.
Viewpoints and Visual Impact Evaluation
Several viewpoints were selected based on the client’s requirements to evaluate the visual effect of the proposed development on significant visual elements in the environment. A range of focal lengths were used to simulate different fields of view. Since human vision and perception can vary, the photomontages are best viewed on-site from the camera’s original location to fully understand the visual impact of the development.
Challenges
Access permissions and timeframes
Due to the project’s tight timeframe and challenges in obtaining timely permission to access the neighbouring properties, CMS Surveyors were unable to collect data (photos and point cloud) directly from these locations.
SOLUTION
3D Laser scanning was conducted from the subject property and surrounding streets utilising a 5 metre tall elevated tripod, allowing dense millimetre-accurate data to be collected over the inaccessible neighbouring properties without physical access.
Establish a true visual context
Photographs supplied by third parties lacked metadata, position and pose information critical to ensuring the visual simulations were accurate and admissible.
SOLUTION
CMS reverse-engineered each image’s orientation, lens characteristics and the position of each camera by using the scanned point cloud and perspective matching algorithms to exactly match the 3D scene’s virtual cameras to the provided photos. The point cloud was then used in a ‘proof’ image to illustrate the reliability of the match.
Varying perception of visual impact
The perception of built form can change dramatically depending on the field of view, focal length, and vantage point. The field of view of human vision is subjective, and how a scene appears on paper, or a screen differs from how it is perceived in reality. To deliver a fair and realistic visual assessment, a range of perspectives needed to be considered.
SOLUTION: Simulated Persepectives and on-site review guidance
Photomontages were created using varied focal lengths to match the images provided. CMS recommends that images be reviewed on-site from their original camera positions for the most accurate real-world perception of scale and impact.
Challenges
Access permissions and timeframes
Due to the project’s tight timeframe and challenges in obtaining timely permission to access the neighbouring properties, CMS Surveyors were unable to collect data (photos and point cloud) directly from these locations.
SOLUTION
3D Laser scanning was conducted from the subject property and surrounding streets utilising a 5 metre tall elevated tripod, allowing dense millimetre-accurate data to be collected over the inaccessible neighbouring properties without physical access.
Establish a true visual context
Photographs supplied by third parties lacked metadata, position and pose information critical to ensuring the visual simulations were accurate and admissible.
SOLUTION
CMS reverse-engineered each image’s orientation, lens characteristics and the position of each camera by using the scanned point cloud and perspective matching algorithms to exactly match the 3D scene’s virtual cameras to the provided photos. The point cloud was then used in a ‘proof’ image to illustrate the reliability of the match.
Varying perception of visual impact
The perception of built form can change dramatically depending on the field of view, focal length, and vantage point. The field of view of human vision is subjective, and how a scene appears on paper, or a screen differs from how it is perceived in reality. To deliver a fair and realistic visual assessment, a range of perspectives needed to be considered.
SOLUTION: Simulated Persepectives and on-site review guidance
Photomontages were created using varied focal lengths to match the images provided. CMS recommends that images be reviewed on-site from their original camera positions for the most accurate real-world perception of scale and impact.
Compliance matters
The client raised concerns regarding the front portion of the proposed dwelling, specifically in relation to the compliant building envelope. They noted that the 3D model exceeds the envelope created with reference to the existing garage’s footprint and floor level. The strict definition of the compliant envelope is that it remains no more than 8.5 meters above the level of the footprint of the existing garage.
CMS Surveyors represented the compliant envelope mass and outline in relation to the proposed 3D model. This approach illustrates to all stakeholders that although part of the building protrudes beyond the compliant envelope, this protrusion does not increase the impact on view lines. The compliant envelope model, rendered with the proposed design, visually demonstrates the minimal effect of the non-compliance why the proposed design would be preferred over a design that exploited the entirety of the compliant envelope.
Conclusion: Success!
The final photomontages and Visual Impact Report enabled the client and design team to move forward with their Visual Impact Assessment with confidence. By grounding every image in survey-grade data and aligning the proposed model precisely within its real-world context, CMS delivered a visual study that stood up to both design and legal scrutiny.
Key outcomes:
- Confirmed minimal view impact and compliance with height restrictions
- Survey-certified visuals suitable for council and Land and Environment Court submission
- Clear representation of the compliant envelope, including critical garage floor pad.
- Improved collaboration across client, design, and planning teams
- Confidence in design decisions, backed by spatially accurate evidence
This clarity helped keep the approval process moving — and the design intent intact.
Ready to explore how CMS Spatial can support your architectural project with a Visual Impact Study? Get in touch with our friendly team for a chat.
We’ll discuss the scope of your project with you in detail, do some analysis at our end, and put together a quote. Fees will reflect the complexity of your project, and the level of detail (LOD) or level of information (LOI) you require.
