Slab edge creates a cold floor band

Heat flows through a concrete perimeter with limited insulation, creating a repeatable cold strip inside.

Failure path

• Step 1: Outdoor temperature falls.
• Step 2: Concrete conducts heat toward the exterior.
• Step 3: The floor edge cools faster than the room center.
• Step 4: Occupants feel a narrow cold band.
• Step 5: High humidity can add surface condensation risk.

What makes this pathway plausible

The timing, location and operating or weather trigger should repeat. A diagram shows a mechanism; evidence from the actual house determines whether it applies.

Best next observation

Record the trigger and compare the nearest materials, components and routes before opening finishes or choosing a repair.

Verification after repair

Recreate the original trigger when safe, then confirm the symptom does not return and affected materials are stable or drying.