Practical research · 9 September 2026
A Repeatable Home Thermal Inspection Photo Log
A useful home thermal survey connects each image to a room, surface and set of conditions. Without that context, a blue corner might be interpreted as a leak one day and missing insulation the next. This worksheet helps you collect repeatable observations for a qualified follow-up.
Define the question before scanning
Choose a specific problem: a cold room, a draft near a frame or an area with visible staining. Record when it occurs and what is different about nearby surfaces. A whole-house collection of colorful photographs is less useful than a small set that tests a clear question.
FLIR notes that a thermal camera reads surface patterns rather than seeing through a wall. Something behind the wall may influence its surface temperature, but the image does not identify the hidden material or prove a cause. Keep the distinction between 'observed temperature pattern' and 'suspected explanation' in every entry.
Source: FLIR: thermal imaging and walls
Record the conditions that could change the picture
Write down indoor and outdoor conditions, heating or cooling operation, recent rain and direct sun on the wall. Note closed blinds, furniture against exterior walls and nearby appliances. These details do not automatically invalidate an image; they identify factors that a later comparison must consider.
Use a repeatable route through the room. Capture a visible photograph of each location, then a focused thermal image. Save the original files with a room identifier rather than relying on screenshots sent through messaging apps. If the camera exports temperature data, preserve that original alongside the picture.
Use a comparison pair
Compare the suspect area with a nearby area of similar construction and surface finish. Avoid treating painted plaster and reflective metal as equivalent references. FLIR's emissivity guidance explains why the same camera settings can produce different apparent results on different surfaces.
Source: FLIR: emissivity and reflected energy
| Entry | What to record |
|---|---|
| Location | Room, wall direction and photograph number |
| Conditions | HVAC state, recent sun/rain and time |
| Reference | Nearby comparable surface and its image |
| Observation | Shape, boundaries and repeatability |
| Follow-up | Moisture check, draft investigation or professional review |
Plan a useful second visit
Return under conditions chosen to test the suspected explanation. For example, an observation affected by direct sunlight deserves a comparison without that influence. Use the same approximate viewpoint and record any changes. A repeat image is most useful when you know which variable you intended to change.
Do not puncture walls, disturb insulation or approach exposed wiring to confirm a picture yourself. Moisture investigations may need an appropriate meter and an inspector who understands the construction. A normal-looking thermal image also does not prove that the wall is dry or well insulated under every condition.
Write a short handoff
Summarize the complaint, image locations, conditions and unresolved question in a few sentences. Include the visible photographs, original thermal files and reference images. A good handoff lets the next person repeat your observation and select a confirmation method. It should not require them to trust a diagnosis made from color alone.