Colossal buildings of reinforced concrete are commonplace today. But the first one west of the Mississippi was in downtown Denver, built in 1907. It housed Charles Boettcher’s Portland cement company, and demonstrated the fireproof qualities of concrete, as Boettcher intentionally set fires in the building that got up to eighteen hundred degrees. In demonstration after demonstration, the concrete floor survived, a dramatic and effective presentation that impressed journalists and business leaders alike.
Reinforced concrete soon became the material of choice for large buildings, and Boettcher’s business, renamed the Ideal Cement Company, became the world’s largest privately-owned firm of its kind. The Ideal Building got a facelift with Cotopaxi travertine in 1927, then housed a succession of banks and ultimately a restaurant, the Broker. The Ideal Building went on the National Historic Register in the late seventies, and is now named The Vault.
