by Catarina Ferreira, AIA
Our 9 unit + office mixed-use building on 9th St NW, in the Shaw and Naylor Court Historic Districts, is well into construction. Underpinning was just completed. It was no easy task.
At first glance, the design proposal looks like a building on top of a building, but in reality, and as far as construction is concerned, it is a building within a building. The construction photos below make this clear.
In order to preserve the existing historic carriage house at the rear of the building, a series of steel beams were introduced in order to create a temporary bridge under which to excavate, underpin foundation walls, and eventually frame the first two stories of the building. Once the existing structure is supported by the new construction under/within it, the steel ‘bridge’ will be removed and construction can progress upwards, in a logical sequence, instead of downwards, as has been the case up to now.
While the end result appears to be simple, it’s easy to underestimate the complexity of building a project such as this.
The end result will be not so much an addition onto a historic building, but rather a sleek, contemporary new building within the original historic structure.