Winter Storm Uri was a brutal lesson in Texas building thermodynamics. Sub-zero temperatures collided with power grid failures, dropping interior home temperatures rapidly. While power was the primary issue, millions of pipes burst specifically because of how the thermal envelope was originally drawn.
The "Vented Attic" Fatal Flaw
Most homes in DFW feature standard blown-in insulation on the attic floor, leaving the actual attic space completely unconditioned and vented to the freezing outside air. Builders frequently run PVC and copper water lines through this freezing attic space, burying them under a few inches of fluff.
When the power failed, the attic instantly dropped to 5°F. The thin insulation over the pipes was useless against hours of sub-zero conduction. The water froze, expanded, and shattered the lines.
Solution 1: The Spray Foam Submarine
Applying Closed-Cell spray foam directly to the roof deck seals the attic entirely. The attic now stays within 10 degrees of the living space. At 10°F outside, the attic remains at 55°F, completely shielding the plumbing lines.
Solution 2: Deep Trenching
If you retain a blown-in fiberglass floor, the plumbing pipes must be structurally lifted and deeply entombed within an R-49+ field of insulation, ensuring they are positioned extremely close to the warm ceiling drywall, utilizing the rising house heat to prevent crystallization.