Thermal Scaling Workflow to compare roofs and buildings in pressurised vs non-pressurised conditions
- Hammer Missions
- Jul 16
- 3 min read
At Hammer Missions, we have created a new workflow within Hammer Hub for you to be able to undertake thermal based comparisons of a building in a pressurized vs non-pressurized conditions.
This workflow enables you to compare pressurized vs non-pressurized buildings stripping out confounding variables—differences in building size, climate, or HVAC systems—and focuses analysis on how airflow, stratification, and leakage dynamics change, enabling you to validate your data models vs reality in a robust, comparable way.
In this tutorial, we will look at how you can use the Compare Function and additional functionality in Hammer Hub to streamline your workflow.
This tutorial assumes that you have
Captured at least 2 Thermal datasets
Captured at least one visual dataset
Generated 2D maps for all 3 datasets
If you're unsure how to create a 2D thermal map in Hammer Missions, please see this article.
Workflow
Step 1: Create a 4D Folder with Project Files
Ensure that you have placed all of the project files (Visual and Thermal) in the same folder, making sure that the folder that you create or use, is a 4D folder.
Folder with 4D option active 
Project Folder for Thermal Comparisons Open the folder and select one of the projects
Select one of the projects within the folder Select the additional projects that you want to compare against
Note: that on the subsequent screen that appears, the projects will appear left to right, (in the sequence by which you selected them). Once the projects are selected, click on the Launch button
Select and launch projects Switch all projects to 2D or 3D view
Switch to 2D view as necessary 
Projects displayed in 2D view Pick a Region of Interest
With the projects displayed in 2D view, click on a region/point of interest in a thermal project to see the closest image to the point you clicked. If you find that the image displayed does not suitably represent the region of interest, you can close the image and select an alternative one (clicking one of the yellow circle + arrow icons).
Selectable images indicated by yellow circle with arrow Scale and Tune Temperature to Bring out Anomalies
The next step is to adjust the temperature scale on the right side of the image, to achieve a good level of contrast. You can also adjust the base level colour palette (between Ironbow /Electric /Jet) by using the liquid drop icon on the left side.
Adjusting the Temperature Scale on Thermal Project 1 Scale in Multiple Projects to Bring out Anomalies
Repeat the step above for your 2nd thermal project (utilising a different colour palette as necessary).
Adjusting the Temperature Scale for Thermal Project 2
Note the palette and temperature scale choices made on an image are also applied to images in close proximity to the region of interest
Opening a corresponding image from your visual project, can provide further clarification or context regarding what the root cause behind the anomaly could be and whether it should be classified as a deficiency.
Annotating images with tags and comments
Both thermal and visual images can be annotated with a label tag(s) and comments that assist with categorisation and reviewing different types of defects.
To add an annotation to any image, hold down the SHIFT key on your keyboard whilst simultaneously dragging your cursor over the area of the image that you wish to highlight.
You can either type a new tag or use an existing tag, if any are available and after adding the tag, there is also an option to add additional comments.
When annotating thermal images, you can also adjust the colour of the annotation area boundary box, to make it more visible against the background.
Moving the mouse cursor over an annotation box, allows you to see the annotation tag as well as any comments.
Summary
In this post, we looked at how to use the Compare and Temperature Scaling functions within Hammer Missions, in order to achieve thermal comparisons between pressurised vs non-pressurized buildings (without potentially confounding variables such as, differences in building size, climate, or HVAC systems).
If you'd like to learn more about how to capture high-quality data and get the most out of your drone flights using our cloud-based platform, please feel free to visit our learning resources.
