In 1918, John Deklewa, Sr., a carpenter and skilled furniture maker, founded a custom home building company in Pittsburgh. The Deklewa name soon became synonymous with quality craftsmanship. In the 1920s and 30s, John Sr. expanded his workforce and became involved in small-scale commercial projects. After World War II, he capitalized on the construction boom and went into partnership with his three sons.

Over the next 25 years, Deklewa began to construct institutional projects such as churches and schools, and by the 1970s, the company had gained experience in several industries and earned a strong reputation throughout the tri-state area. During this time, a third generation of Deklewa sons joined the team, and in 1982, they incorporated and further diversified the company’s capabilities, performing healthcare, industrial and retail construction.