What Is Driveway Infrared Thermography?
Driveway Infrared Thermography is a non-invasive inspection method that uses a high-resolution thermal camera to “see” temperature differences across your driveway’s surface. Those temperature patterns reveal hidden problems—most importantly subsurface voids—long before you notice a dip, crack, or pothole.
Think of it as an X-ray for your pavement, but without radiation, drilling, or guesswork. A certified technician scans the driveway in minutes, then produces a color-coded map that pinpoints exactly where the base layer has eroded or settled. Early detection lets you fix small voids for a few hundred dollars instead of rebuilding entire sections for thousands.
Why Subsurface Voids Spell Trouble
How Voids Form Under a Driveway
- Water infiltration through hairline cracks or unsealed joints washes away fines in the base.
- Freeze–thaw cycles expand cracks and pump soil out from beneath.
- Burrowing pests, tree-root decay, or poor compaction during original install leave hollow spots.
Warning Signs Homeowners Miss
By the time you see a visible dip or hear a hollow “thud” when you tap the surface, the void has grown large enough to threaten structural integrity. Infrared thermography spots the temperature signature of that empty space weeks or even years earlier.
Safety & Liability
A sudden sinkhole under a parked car or a tripping hazard for visitors can turn into an insurance claim. Detecting voids early keeps your property safe and limits your liability.
How Driveway Infrared Thermography Works
The Science in Plain English
Air pockets inside a void hold heat differently than solid stone and asphalt. During the day, the sun warms the surface; at night, solid areas release heat faster than hollow spots. A thermal camera records these subtle temperature differences—sometimes as small as 0.1 °C—and converts them into an image where colder areas appear blue and warmer areas red or yellow.
Step-by-Step Scan Process
- Weather check: Ideal conditions are a clear, dry evening within 24 h of sunshine. Wind speeds below 10 mph prevent false cooling.
- Surface sweep: Debris, leaves, and parked cars are removed so the entire driveway is exposed.
- Thermal scan: The operator walks the driveway with a handheld camera or mounts one on a drone for large areas. Images are taken every few feet, overlapping for complete coverage.
- Mark-up: Suspicious cold or hot spots are spray-painted directly on the surface so you can see the exact boundaries.
- Report: You receive a PDF map with temperature scales, photos, and repair recommendations.
Limitations to Know
Thermography can’t measure the depth of a void—only its footprint. If depth data is critical (for example, under a thick concrete slab), the technician may follow up with ground-penetrating radar (GPR) or a small core drill.
Top Benefits for Homeowners
- Zero damage: No drilling, coring, or chemicals touch your driveway.
- Speed: A typical two-car driveway scan takes 15–30 min.
- Cost-effective: Early repairs (polyurethane foam injection) cost 50–70 % less than full-depth patching.
- Planning tool: Use the report to get apples-to-apples bids from contractors who now know the exact problem areas.
- Pre-sale confidence: Attach the report to your real-estate disclosure to prove proactive maintenance.
When Should You Schedule a Scan?
Seasonal Timing
Spring and fall give the biggest temperature swings between day and night, improving contrast. Mid-summer afternoons can work if you wait until after sunset. Winter scans are tricky unless the driveway is clear of snow and ice for at least 48 h.
Life-Cycle Milestones
- New build: Scan before the builder’s warranty expires to catch compaction issues.
- Age 7–10: First signs of aggregate polishing and micro-cracking appear.
- Before sealcoating: Verify the base is sound so you aren’t sealing water into hidden voids.
- After heavy flooding or seismic activity: Ensure soil wasn’t washed away or shifted.
DIY Thermal Camera vs. Professional Service
What a $400 Handheld Camera Can’t Do
Big-box-store infrared cameras have low resolution (80 × 60 pixels) and no emissivity calibration for asphalt. They’re fun for finding missing insulation, but they’ll miss a 2-inch void under a black driveway because the temperature delta is too small.
Certified Thermographer Advantages
- 640 × 512 pixel cameras that detect 0.05 °C differences.
- Training to distinguish voids from shade, tire tracks, or surface moisture.
- Errors-and-omissions insurance that covers misdiagnosis.
- Software that overlays thermal and visible-light images for precise marking.
Rule of thumb: If the repair budget is above $500, spend the extra $150–$250 for a pro scan. You’ll save more than that by avoiding unnecessary digging.
Typical Pricing in 2024
| Driveway Size | Scan Only | Scan + GPR Cross-Section | Scan + Small Foam Injection* |
|---|---|---|---|
| Up to 600 ft² (1-car) | $150–$200 | $300–$350 | $550–$750 |
| 600–1,200 ft² (2-car) | $200–$275 | $375–$450 | $750–$1,100 |
| 1,200–2,000 ft² (3-car or circular) | $275–$350 | $450–$550 | $1,100–$1,500 |
*Foam price assumes 2–3 cubic ft of void; larger voids scaled per cubic ft.
Money-Saving Tips
- Bundle with neighbors: Many contractors drop the per-property price 20 % for three or more driveways on the same street.
- Ask for a “drive-by” rate if you only need the scan and will handle repairs yourself.
- Request thermal images in digital format only—printed posters add $25–$40.
What Happens After the Scan?
Reading Your Report
Look for these key items:
- Delta-T: Temperature difference between suspect and solid areas. Anything above 2 °C warrants attention.
- Area outline: Should be drawn to scale so you can measure square footage for bids.
- Priority code: Good reports label voids A (monitor), B (repair within 6 mo), or C (repair within 30 days).
Repair Options Explained
- Polyurethane foam injection: Two-part liquid expands 20×, fills voids, and cures in 15 min. Driveway ready for cars in 30 min.
- Slurry grouting: Cementitious mix pumped under low pressure. Cheaper than foam but requires 24 h cure and may crack again if base soils shift.
- Partial reconstruction: Cut and remove the affected section, re-compact base, and repave. Necessary when the asphalt itself is brittle or the void exceeds 4 ft in any direction.
Preventing Future Voids
Seal Cracks Early
Apply a hot-rubberized crack sealant to any opening wider than ¼-inch before water gets in. Budget $0.75–$1.00 per linear foot for professional sealing.
Control Water Flow
- Install gutter downspout extensions that dump water at least 5 ft from the driveway edge.
- Grade landscaping so soil slopes 1 in. per ft away from the pavement.
- Add a French drain along the lower edge if the driveway sits at the bottom of a hill.
Limit Point Loads
Garbage trucks and moving vans exert 3–4× the psi of a passenger car. Place plywood sheets under their wheels or schedule deliveries when the base is driest (late summer).
Frequently Asked Questions
No. The camera only records natural heat radiation; it emits nothing. The operator walks on the surface with normal footwear—no drills, no chemicals, no high-pressure equipment.
Certified techs overlay the thermal image on a visible-light photo, then trace the void outline with spray paint or chalk accurate to within 1 inch. Most also provide GPS coordinates if you request them.
Yes. A dated, third-party infrared report is admissible in most small-claims or mediation cases. Pair it with repair quotes to show measurable damages.
Standard policies exclude “settling, cracking, or bulging” unless caused by a covered peril like a water-main break. Ask your adjuster; if the void resulted from a sudden plumbing leak, you may be reimbursed.