Tree House sits on a cul-de-sac at the end of a mature subdivision in Wilmington, Delaware, USA. It is filled with century-old deciduous trees, which form a magnificent canopy 150 feet above the site.

A stream runs around the house, and because of the potential for flooding, the buildable area is quite small.

All pictures and content are courtesy of the Architects

The decision to preserve all the trees on the site, with the constraints of the hundred-year flood plain on the building pad, decided the vertical form of the house.


The main living area is on the second level, while the main bedroom and ensuite occupy the entire third level. These raised spaces give one the feeling of being in the trees, of being part of the canopy itself. Other spaces include a spare bedroom at the garage level and a study on the second floor.


The inside stairs were designed by Sander Architects and fabricated at the performance stage shop where the client works. They are made of 1/2” aluminum plate, with two treads in each unit.

Horizontal windows encircle the house, providing select views into the landscape. In contrast to these small views, a great wrapping window in the double-height Living Room provides a dominant diagonal focus for the house, and leads views into the deep woods to the northeast.

Two exterior stairs access the house. A front entrance stair, cantilevered away from the façade, enters through a trio of trees. This stair has bar grate steps that provide a view of the stream below and also discourage snow build-up. On the East façade, a spiral stair wraps up from the ground level to the roof deck which doubles as an outdoor living space for tree top entertaining.