St. Louis Housing Stock: The Age of Brick (and Lead)

Key Takeaways

The Profile: 48% of St. Louis City homes were built before 1939. St. Louis County is dominated by 1950s-60s ranches.
The Foundation Threat: St. Louis's expansive clay soil wreaks havoc on unreinforced poured concrete (common in the 50s) and limestone foundations (common in the 20s).
The Plumbing Time Bomb: If your home was built before 1960 and hasn't been repiped, you likely have galvanized steel supply lines that are rusting from the inside out.
The Brick Factor: Tuckpointing isn't cosmetic; it's structural. Missing mortar leads to water infiltration and mold.

Homes built between 1920 and 1960 almost exclusively used galvanized steel pipes.

The Problem: Zinc coating wears off after 40-50 years. Rust builds up, restricting flow (low water pressure) and eventually causing bursts.
The Fix: 2025 Repiping costs avg $4,000 - $8,000 for a standard bungalow. PEX is the preferred replacement material.

St. Louis sits on highly plastic clay soil that expands when wet and shrinks when dry.

The Problem: This seasonal movement cracks foundations. In 1950s ranches (like those in Affton or Florissant), horizontal cracks are a sign of hydrostatic pressure bowing the walls inward.
The Fix: Determine if it's "Settling" (vertical cracks) or "Bowing" (horizontal). Bowing often requires carbon fiber straps or steel piers.

Knob & Tube (Pre-1940): Uninsurable. Must be replaced immediately.
Un-grounded Outlets (1950s): Many mid-century homes have 2-prong outlets. They lack a ground wire, risking electronics and safety.

Panel Upgrade (Heavy Up): Moving from 100-amp to 200-amp service to handle EVs and heat pumps.
Sewer Lateral Liner: St. Louis clay pipes crack. Trenchless lining saves your yard and costs ~50% less than digging.
Insulation Injection: Most brick bungalows have ZERO wall insulation. Injecting foam or cellulose can drop energy bills by 30%.

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