As building issues get more complex and construction costs rise, making the right decision for our built environment has become more critical than ever.
Every place has a unique history to its habitat and culture. Historical preservation helps a city become more competitive in terms of bringing its unique cultural context to visitors. They also function as a 'living' artifact that can assist in passing historical lessons generation after generation.
The Old Town of Eureka in California is an excellent example of how the local community revitalizes its place by offering culture-enrich walking tours. From the town's oldest post office to the most prominent Carson Block commercial building, Eureka's walking tour, just like its name, gave visitors an ah-ha moment back to one of the nation's glorious times.
Another example is Faneuil Hall in Boston, Massachusetts. Initially built by artist John Simbert in 1740-1742, Faneuil Hall has undergone many different uses through the centuries. It now stands still as the local's most popular meetup place and an essential stop on the Freedom Trial.
Because of the historical significance of many places, historic preservation became an integral part of the urban planning profession; universities began to make it part of the curriculum in the 1960s. Nowadays, many places have benefited from the federal tax-credit program, and portions of their historic fabric could remain.
Though many concerns and criticism of historic preservation lean on its construction cost, many communities are still eager to preserve their places and identity. So, how can we know if those buildings are worth keeping?
First and foremost, before all the historic preservation work is done, we need to identify those buildings, their neighborhood setting, or context, then evaluate them to see if they are worth going through a preservation process. Here are the steps to determine the potential historic preservation projects. They are also part of the building analysis and programming phase.
I. Determine the eligibility of a property for National Historic Designation.
The historic preservation service of the National Park Services has developed a wealth of information regarding historic landmarks as well as historic preservation in general. The property owner can check this map to see if the property is a historic landmark or located in the designated historic district. Suppose the owner thinks their properties have historical significance and wants to prove this to National Park Services (NPS). In that case, the owner can check these six criteria (of national significance) to see if the property is qualified.
For example, the Kensington historic district was filed for national historic place registration back in 1978. The local community and the Kensington Historical Society's preservation committee thought that area was a 'turn-of-the-century' cultural asset in the region. Together with Maryland Historical Trust staff, they delineate a boundary for keeping the historical significance in place.
II. Evaluating Historic Structure
Once the owner sees whether the property is a historic landmark or just an old building that the owner would like to reuse while maintaining its historical characteristics, the owner could follow the guidelines to treat the structure properly. Choosing the most appropriate treatment for a building requires careful decision-making about its historical significance, physical condition, proposed uses, and other mandatory regulation such as accessibility and life safety code.
There are four primary approaches to treating historic property: Preservation, Rehabilitation, Restoration, and Reconstruction.
Preservation: This approach keeps all historic structures intact through protection, maintenance, and repair without alterations. That will reflect a building's evolution over time.
Rehabilitation: the existing building needs this approach after determining the requirements of a new program cannot be successfully met. The additional structure should be designed so the essential form and integrity of the historical significance would remain if the expansion is removed.
Restoration: This approach emphasizes the building's significance at a particular time in its history. That method keeps material similarity during the represented era and removes evidence from the other period.
For example, the Carson Block Building was built in 1892 with red brick and terra cotta. In the 1920s, people added white stucco to the exterior to modernize the building. During the upgrade and restoration in 2016, the owner decided to remove layers of stucco. The building also recreated the missing corner turret and sensitively added seismic reinforcement on its upper floor.
Reconstruction: This is the least historically accurate approach. It replicates the non-surviving portion of the property or recreates the vanished structure for its interpretive purpose. For example, the Tyron Palace in North Carolina was designed and built from 1767 to 1770. The facility was destroyed by fire in 1798. The palace was reconstructed in 1959 based on its original foundation, found five feet below the street level.
III. Evaluating Functional Requirement
This step happens almost simultaneously when determining historical significance because before finalizing these four approaches, it is critical for owners to evaluate the current space need and other functional requirements. Here are the highlights on how to evaluate this requirement and programming.
a. determine space needs
What is the number of people to use in the building?
What is the required clearance for specific equipment placed in the building?
What kind of activities will happen in the building?
b. determine the total building area
The individual activities decided will make up the net area of a facility. This area does not include space for general circulation between rooms or mechanical space. Therefore, the planner needs to factor the efficiency ratio (or net-to-gross ratio) into the 'net' area number. By doing so, they will come up with a gross building square feet and use that area to see if the building needs to undergo rehabilitation in a historic property.
c. determine space relation
When deciding the final program, the planner has to have the correct size for the activities in the bldg. Still, the area must also be located within a suitable adjacency to maintain its functional relationship. The matrix and the adjacency diagram are commonly used to explain the spatial relation to the owner. However, the best approach for a historic building is to understand and analyze its existing space and define the program simultaneously. For example, many historic buildings are made of masonry, and it is challenging to move existing demising walls to meet the new program. In a number of circumstances, it will be cost-effective to identify a suitable program to meet specific square feet or geometry in a historic property.
What's Next?
We have been alerted that the urban population will increase to 68% of the total world population by 2050, and there are forty-three megacities with more than 10 million people projected by 2030. At some point in the next decade, historic preservation will no longer be a cultural significance issue or cost concern, but rather how we can smart invest our current estate in meeting the future urban population demand. We might need to look at our land consumption seriously; regardless of a 'low-density' sprawl (like those in the United States) or a 'high-density sprawl' (like those in China), we need to find a principle maneuvering between those old and new buildings.
As our history evolves, our 'historic preservation' principles must evolve too.
Notes and References:
Many buildings of Eureka’s walking tour were built around 1880s. From Thomas Edison to Alexander Graham Bell, the United States has experienced its unprecedented technology boom: the electric streetlight was installed, the first the practical telephone was also patented. That was the era when lights and sounds transmitted across the country.
According to Kensington's National Historic Registration filing document, the area was "to include the highest incidence of buildings and structures which meet the criteria for inclusion in the National Register of Historic Places, either individually or in group, and contribute to the historical and cultural character of the district."
Detailed information regarding The four approach to historic building please refer to: The Secretary of the Interior’s Standards for Treatment of Historic Properties with Guidelines for Preserving, Rehabilitating, Restoring and Reconstructing Historic Buildings, Department of Interior and National Park Service, 2017.
Many demising wall function as structural support in historic buildings, thus it is challenging to remove them and still remain structural integrity.
The building efficiency often range from 60% to 80%, though some use may result in efficiencies outside this range. (10-15). When a owner plan to lease space in an existing facility rather than construct a new building, the owner needs to decide the rentable area needed to accommodate the new program. The rentable area is always greater than the basic programmed usable are because include circulation and other mechanical or service spaces.