Building trust since 2003.

From a garage in the Jordaan to 340+ projects

In 2003, Willem van der Berg and a single carpenter started renovating apartments in Amsterdam's Jordaan neighbourhood. The work was small but the standard was high — and word spread. Within three years, Cornerstone had a team of twelve and its first commercial contract.

Two decades later, we operate from our Amsterdam headquarters, employ 120+ professionals, and have delivered over 340 projects across residential, commercial, heritage, and sustainable construction. The scale has changed, but the principle hasn't: every project gets our full attention and our highest standard.