Adaptive Re-Use: Repurposing existing building stock

Adaptive reuse seeks to deal effectively with the issues of conservation and heritage policies. While old buildings may become unsuitable for their programmatic requirements, as progress in technology, politics and economics moves faster than the built environment, adaptive reuse comes in as a sustainable option for the reclamation of sites. In many situations, the types of buildings most likely to become subjects of adaptive reuse include: industrial buildings, as cities become gentrified and the process of manufacture moves away from city; political buildings, such as palaces and buildings which cannot support current and future visitors of the site; and community buildings such as churches or schools where the use has changed over time.

Adaptive reuse is seen as an effective way of reducing urban sprawl and environmental impact. By reusing an existing structure within a site, the energy required to create these spaces is lessened, as is the material waste that comes from destroying old sites and rebuilding using new materials. Through adaptive reuse old, unoccupied buildings can become suitable sites for many different types of use.

Criteria to Consider

While the process of adaptive reuse is a decision often made purely by companies establishing a particular brand or presence, there are often criteria for deciding whether a building should be conserved and reused or just demolished for the area of land it occupies. Some of these determining criteria include:

• The societal value of a given site; that is the importance of the use of a site to the community or visitors’ use;
• The potential for the reuse of a particular site; the physical damage sustained to the site and its support of future use, the character of the existing site in terms of the proposed reuse;
• The historical importance of the site; in terms of both physicality of the street-scape and the area, as well as the site in the community’s understand of the past; and,
• The natural ecological conditions of the site; whether the site is suitable climatically or can support the proposed environmental work needed in the site.

Advantages of Adaptive Reuse

With the debate of adaptive reuse as a sustainable avenue in the development of key sites, there are many advantages to using certain sites for redevelopment. Some of these advantages include the site’s location; in many cases, historical sites are often located in the centers of large cities due to the spatial development of a given area, these buildings can often be heritage-listed and therefore sold as an entity, rather than just for the land that they occupy, which the new tenants then have to retrofit the building for their particular purpose. Older buildings also often have a specific period character through the detailing and joinery of their constructed eras that newer or reconstructed developments lack, in certain cases, such as the hospitality industry; the grand character of a site can influence the feel of their building and are used for maximum potential to enhance the site’s physical attractiveness to a client.

Barriers to Adaptive Reuse

As mentioned above, adaptive reuse sometimes isn’t the most viable option for all historic sites. For some sites that have been left alone to decay by neglect, the physical damage of the site can render the site unusable both in terms of the cost to repair the damage as well as unsafe by government standards. Sites contaminated by old materials such as asbestos also become unviable for the process of adaptive reuse.

Providing Handicap Accessibility

Historically, most buildings and landscapes were not designed to be readily accessible for people with disabilities. In recent years, however, emphasis has been placed on preserving historically significant properties, and on making these properties-and the activities within them-more accessible to people with disabilities. With the passage of the Americans with Disabilities Act in 1990, access to properties open to the public is now a civil right. Modifications to historic properties to increase accessibility may be as simple as a small, inexpensive ramp to overcome one entrance step, or may involve changes to exterior and interior features.

A three-step approach is recommended to identify and implement accessibility modifications that will protect the integrity and historic character of historic properties:

1) Review the historical significance of the property and identify character-defining features;

2) Assess the property's existing and required level of accessibility; and,

3) Evaluate accessibility options within a preservation context.

It is a challenge to evaluate properties thoroughly, to identify the applicable accessibility requirements, to explore alternatives and to implement solutions that provide independent access and are consistent with accepted historic preservation standards. Solutions for accessibility should not destroy a property's significant materials, features and spaces, but should increase accessibility as much as possible.

Upgrade of Heating, Ventilating and Cooling Systems in Historic Buildings

The successful integration of new systems in historic buildings can be challenging. Meeting modern HVAC requirements for human comfort or installing controlled climates for museum collections or for the operation of complex computer equipment can result in both visual and physical damage to historic resources. Owners of historic buildings must be aware that the final result will involve balancing multiple needs; no perfect heating, ventilating, and air conditioning system exists. In undertaking changes to historic buildings, it is best to have the advice and input of trained professionals who can:

• assess the condition of the historic building,
• evaluate the significant elements that should be preserved or reused,
• prioritize the preservation objectives,
• understand the impact of new interior climate conditions on historic materials
• integrate preservation with mechanical and code requirements,
• maximize the advantages of various new or upgraded mechanical systems,
• understand the visual and physical impact of various installations,
• identify maintenance and monitoring requirements for new or upgraded systems, and,
• plan for the future removal or replacement of the system.

Too often the presumed climate needs of the occupants or collections can be detrimental to the long-term preservation of the building. With a careful balance between the preservation needs of the building and the interior temperature and humidity needs of the occupants, a successful project can result.

Existing mechanical systems should be regularly inspected and maintained by a qualified HVAC contractor on a semi-annual basis. As plans are developed for the re-purposing of institutional structures, an upgrade to the mechanical system and addition of cooling may be considered. A mechanical systems engineering firm with a proven track record in historic structures must be consulted as the introduction of new systems in older buildings is not without problems--historic buildings are not easily adapted to house modern precision mechanical systems.

Careful planning must be provided early on to ensure that decisions made during the design and installation phases of a new system are appropriate. The size of the new system and needed output CANNOT be accurately calculated until AFTER improvements to the envelope (such as insulation an improvements to the fenestration) are accounted for. Since new mechanical and other related systems, such as electrical and fire suppression, can use up to 10% of a building's square footage and 30%-40% of an overall rehabilitation budget, decisions must be made in a systematic and coordinated manner. The installation of inappropriate mechanical systems may result in any or all of the following:

• large sections of historic materials are removed to install or house new systems,
• historic structural systems are weakened by carrying the weight of, and sustaining vibrations from, large equipment,
• moisture introduced into the building as part of a new system migrates into historic materials and causes damage, including biodegradation, freeze/thaw action, and surface staining,
• exterior cladding or interior finishes are stripped to install new vapor barriers and insulation,
• historic finishes, features, and spaces are altered by dropped ceilings and boxed chases or by poorly located grilles, registers, and equipment,
• systems that are too large or too small are installed before there is a clearly planned use or a new tenant,

For historic properties it is critical to understand what spaces, features, and finishes are historic in the building, what should be retained, and what the realistic heating, ventilating, and cooling needs are for the building, its occupants and its contents. A systematic approach, involving preservation planning, preservation design, and a follow-up program of monitoring and maintenance, can ensure that new systems are successfully added--or existing systems are suitably upgraded--while preserving the historic integrity of the building.

Summary

No set formula exists for determining what type of mechanical system is best for a specific building. Each building and its needs must be evaluated separately. Some buildings will be so significant that every effort must be made to protect the historic materials and systems in place with minimal intrusion from new systems. Some buildings will have museum collections that need special climate control. In such cases, curatorial needs must be considered--but not to the ultimate detriment of the historic building resource. Other buildings will be rehabilitated for commercial use. For them, a variety of systems might be acceptable, as long as significant spaces, features, and finishes are retained. Most mechanical systems require upgrading or replacement within 15-30 years due to wear and tear or the availability of improved technology. Therefore, historic buildings should not be greatly altered or otherwise sacrificed in an effort to meet short-term systems objectives.

Adaptive reuse seeks to deal effectively with the issues of conservation and heritage policies. While old buildings may become unsuitable for their programmatic requirements, as progress in technology, politics and economics moves faster than the built environment, adaptive reuse comes in as a sustainable option for the reclamation of sites. In many situations, the types of buildings most likely to become subjects of adaptive reuse include: industrial buildings, as cities become gentrified and the process of manufacture moves away from city; political buildings, such as palaces and buildings which cannot support current and future visitors of the site; and community buildings such as churches or schools where the use has changed over time.  CONTACT US  to discuss adaptively reusing existing building stock to meet your company or institution's program needs.