Buildings are now, and always have been informed by their context. As AEC professionals it’s part of the job to develop a strategy, design, and construction details that suit the specific site you are working with. Since the mass adoption of BIM in professional practice site models are moving from physical to digital, and are often shared between teams. Many practices build these themselves, taking advantage of tools in e.g. Revit to produce terrain models from 2D DWGs with contour lines, while others are taking the next step in exploring services like Cetopo to fully automate this process, adding a level of complexity which is impossible, or incredibly time consuming otherwise. This article will compare the process of building models manually, vs. using Cetopo.
Benefits of DIY site models
Thanks to advancements in BIM software, it is possible to build your own terrain models, based on 2D DWGs, which you will likely buy for Planning Applications anyway. These tools are handy for rough models, but can be time consuming if you aren’t a very advanced user. Highlights of this method include:
- Smaller initial costs (only need to pay for DWG)
- Experienced BIM users can build terrain models
Benefits of Cetopo
Having launched in the Nordics in 2020, and expanded to the UK and Netherlands in 2023, Cetopo comes backed by 1000s of happy users. It focuses on saving Architects time by automatically compiling information and providing users with all of the information they need, instantly, in one easy-to-use package. Highlights include:
- Instant access to combined models inc. terrain, buildings, roads, paths, trees
- Full native editability in all software
- Massive time savings
- Easy to use, no learning curve
- 2D DWGs included
A Cetopo model of the same area as above, in Revit
The article continues below.
So how do the workflows compare?
The crucial difference is that Cetopo collates multiple data sources and allows users to access all of the information they need in one place – in any format they like; while building models yourself involves searching around for information and manually building roads, trees, building etc by eye.
DIY
- Buy 2D DWG from OS Licensed Partner
- Take or buy photos of site
- Use DWG to toposolid tools in Revit to generate 3D model of topography
- Manually build models based on building footprints and photos
- Manually place tree models
- Adding subdivisions for roads and paths to the toposolid manually.
- Repeat this process for each programme (e.g. Revit, AutoCAD)
Time: 6-12 Hrs
Cetopo
- Select project area
- Download model in all required formats
- Use in any/all software
- Save selected area for later use
Time: 5 mins
How can Architects use the models?
Editable: Models are designed to sit in your workflow, and are fully editable in all major architectural software. Buildings, roads, paths, terrain and trees, are all individual models grouped in layers for ease of use and editability.
Lightweight: Cetopo’s smart algorithm optimises models to run quickly in all design software, regardless of size.
Rendering Optimised: Features include compatibility with Enscape assets, and ability to automatically replace tree models with Enscape trees (or .rfa trees in Revit)
How does accuracy compare?
Cetopo models are based on regularly updated data, and are very accurate. Detail levels vary per country, but here are the UK levels for example:
Terrain: Based on UK Gov LIDAR, accurate to +0.15m, continually updated.
Buildings: Based on OSMM and LIDAR, LOD2.
Roads: Based on OSMM, includes paths and pavements, updated every 6 weeks.
Trees: Based on LIDAR and UK Forestry, accurate in size and placement.
DIY models can vary massively in terms of accuracy, depending on the available information or skill levels, but could be something like:
Terrain: Based on 3D contours, accurate to contour spacing – typically 0.25m.
Buildings: Based on 2D footprints, photographs, and possibly 2D sections. Can be very prone to human error and guesswork.
Roads: Based on 2D plans.
Trees: Usually placed based on photographs, fairly inaccurate.
What does it cost?
Cetopo runs a subscription based service, with bulk discounts for more projects. Projects start at around €200 including access to all 3D and 2D data instantly, in as many formats as required. Customers can also download receipts for each project, allowing them to offset the cost to the client, or include it in their fee.
The DIY method may have less outset costs – you might only need to buy a 2D drawing, but could cost you up to a couple of days of one skilled person’s work time, and therefore incurs wasted salary costs. This cost will vary depending on the complexity and size of the project area.
TLDR: Should I use Cetopo?
As described above, the decision whether or not to switch to an automated site modeller such as Cetopo depends largely on how much time you spend compiling and building models yourself.
If you’re only working with very small sites, that you simply need as a backdrop to your design then DIY is maybe good enough for you. However, Architects who want to easily create stunning visualisations, work effortlessly with site models across modelling softwares and generally keep their fingers on the pulse might want to look a little closer at Cetopo.
Stick with DIY if:
- You only work in 2D
- You are happy to use salary costs to build models
Use Cetopo if:
- You work across multiple softwares and file formats
- You want to control and edit your 3D model
- You work on more than 2 projects/year
- You work on projects with sites over 1-2Ha
- You want to use your time well
- Accuracy is important to you