No. 43 of Campo das Cebolas is a remarkable example of Pombaline architecture, in a 5-storey building facing the Tagus River. Despite having only one front, the fact that it is shallow and facing south makes it very bright.
We found it in a reasonable state of repair in terms of the structure, but the adaptation of some fractions in the offices of shipping agencies left serious scars.
Originally, the rectangular building was divided in half by stairs and separated two apartments of large typologies.
The program provided for the division into smaller apartments. For this, we chose to create a new T1 fraction in front of the stairs, taking advantage of an entrance that already existed, and leaving the two lateral fractions with larger dimensions and with T2 typology.  The structure was maintained and so were the corridors that define the interior spaces.
An elevator was placed adjacent to the stairs, with an exit to the main landing.
The roof was completely redone, with the same slope and in a single plane, but dormers were introduced, aligned with the lower spans. This allowed a better use of the attic space and two special apartments were installed there, in open space, with a sloping roof and with the metal structure in view. 
It was decided to install solar panels on the roof since it is a single large water facing south and the panels could be coplanar with the tiles.
The general principle of the intervention was to recover the primitive essence of the Pombaline building, both in terms of materials and constructive details. We reused all shutters and doors, the tiles that covered the inside of the chimneys and the stone we found was used for the flooring in the elevator area on the entrance floor.
The new covering materials also respect the building's construction period: wood, stone or tile. 
During archaeological excavations, the Roman Wall was found in the place where the elevator was planned.  It was not possible to leave it in sight, but another section of this well-located and characterized National Monument remained.