The European in me would have sought a clear distinction between old and new, so that was the starting point. However, in this case it was not just a matter of design a new building next to the old one. The original building required a significant amount of repair work and its 9th St elevation (the actual facade based on the building’s address) lacked coherence. Several poorly-designed alterations had been made over the last 170 years or so.
Sometimes the answer is not about black vs. white but rather shades of grey. The ultimate solution is a hybrid building that blurs the line between old and new just enough to make a passer-by do a double take. It looks like one building from farther away, like two up close. This allowed the integrity of the historic structure to be maintained, allowed us to propose a clean addition that is distinct yet compatible, and most importantly, one does not try to mimic/reproduce the existing building.
Often, in Washington DC, the tendency is to mimic the appearance of historic structures or to propose a slightly watered down version of them in order to try to achieve compatibility. That erasure of history, by replicating a historic language in the present, reduces the proposed and the original building to nothing more than their appearance. To me, architecture is about poetry, creating a rich experience by manipulating the grey zone, not about superficiality/appearance. Historic districts are first and foremost about a coherent atmosphere.
So how did we achieve a coherent atmosphere/ historic compatibility in this case?
My number one go-to strategy in historic district is always simplicity: simple massing, discrete character.
Then comes soul/personality: In this case, is it one building or two? It seemed important to maintain that duality. Also, a raw, slightly industrial aesthetic is proposed in both parts of the building. I feel this is compatible with the character of this particular historic district, where alleys are streets, carriage houses are homes, and just a dash of grit prevails.
Then comes continuity of materials: same brick color/size, same siding material on bay windows, same window color, despite different geometry/size.