Historical Preservation

Cobeal helps you choose a system and/or equipment that is appropriate for your building. Museums and historical buildings have different climatic needs than office buildings. Our goal is to help you: 

• Retain original architecture configurations, surfaces, and finishes, such as vaulted and ornamental ceilings, pilasters, and capitals. 
• Retain any existing historically significant features, such as original registers, radiators, escutcheons, radiator enclosures, etc. by reusing existing ductwork, vents/air intakes, and janitorial closets. 
• If disturbance is unavoidable, the replacement system should match the design, color, texture, and materials of the original. 
• Match the finished appearance of the space to the original. 
• Ensure that the addition of HVAC systems and other repairs will not corrupt the building's structural integrity. 
• Cobeal gives careful consideration to the introduction of humidification systems into historic buildings. Adding humidification can damage building envelopes without perfectly sealed vapor barriers, which are difficult to achieve in existing buildings. Uses such as museums in historic structures often find themselves in conflict between the needs of occupancy versus the capability of the building to achieve desired environmental conditions. 

The following abridged list of aspects are considered: 

• Distribution System
  • Avoiding the need for new ductwork, especially in lobbies, corridors, and other circulation spaces, Cobeal examines ductless alternatives such as split systems and pipe systems with reuse of existing ducts for ventilation. 
  • When new ductwork is unavoidable, Cobeal disturbs as little original fabric as possible, this also minimizes the visual impact. 
    • Cobeal accommodates air distribution by avoiding the reconfiguration of ceilings (e.g., suspended ceilings). 
    • When possible, Cobeal installs in secondary spaces such as attics or basements. If service areas are not available, systems are carefully placed in secondary areas, never in primary spaces, and away from window heads. 
    • Exterior appearance is preserved by retaining full window height. 
    • Ceilings are carefully configured to avoid obscuring the full height of windows and interior or exterior transoms.
    • Rather than puncturing decorative elements, the position of ductwork is moved. This retains decorative millwork and other character-defining features. 
    • Cobeal explores zoning using multiple, smaller ducts, rather than a single, larger profile duct system. The careful configuration of ductwork, which should be as flat as possible, avoids disrupting the symmetry of the space. 
    • Whenever possible, running ductwork along or across corridors is avoided. 
    • In some cases, exposed ductwork may be appropriate, such as in industrial or other utilitarian buildings, or spaces with vaulted or other decorative ceilings that would otherwise have to be obscured. 
• Building Envelope
  • Cobeal installs security doors, locks and/or stops, if required to control tenant use. Whenever possible, window operability is retained.
  • Whenever possible, operational windows are used for natural ventilation during spring and fall months. Cobeal uses weather stripping and insulates doors and windows, instead of replacing or sealing windows. 
  • Cobeal considers the architect's original energy conservation methods, such as operable windows, porches, overhangs, etc. Cobeal incorporates these features into the overall energy conservation plan. 
  • Whenever possible, Cobeal aims to retain original ventilation systems (e.g. attic vents, crawl space, and airflow patterns). 
  • Cobeal carefully considers insulation options; ensuring that the chosen method/materials will not create condensation in a building's interior. 
  • In certain climatic conditions, Cobeal may incorporate a vapor retarder to reduce the moisture contribution from interior spaces. However, in well insulated walls during cold weather the benefits are minimal. Vapor Retarders must be continuous to work properly, which is often difficult in existing or historic buildings. Careful analysis is considered prior to incorporating this approach. 
  • Cobeal helps you maintain good breathability/permeability of the envelope by being mindful of the original structure's inherent tolerance to moisture. 
• Equipment 
  • Cobeal installs air handlers and other equipment in locations that will least affect building occupants and activities (e.g. vibration and noise). 
  • Cobeal installs wall or ceiling mounted equipment in secondary or tertiary spaces. 
  • Landscaping is a low cost method of camouflaging new HVAC equipment. Remotely locating new equipment may be necessary if there are archaeological or historic landscape features to consider. 
  • Roof-mounted equipment is hidden from the street and other obvious vantage points. Site studies can indicate ideal locations. 
  • Contact Cobeal for a detailed discussion of installing HVAC equipment in your historical building. 

Information technology systems are complex and constantly changing. These systems have exponentially increased the need for easily accessible wiring raceways. Although not appropriate for all buildings and spaces, some historic buildings request this approach to retain ornamental ceilings and features: 

• Wireless solutions are the first consideration. 
• To the greatest extent possible, Cobeal reuses existing conduit and wiring chases. 
• For small and/or highly significant buildings, Cobeal often recommends locating computer servers off-site. 
• Cobeal designs for the flexibility of the layout. 
• Cobeal recommends installing computer and IT wiring that can be easily reversed. 
• Cobeal recommends locating servers in appropriate climate-controlled tertiary spaces (basements or existing windowless rooms) to minimize intrusion. 
• Cobeal avoids altering doors and windows for climate control unless absolutely necessary, or unless security is an issue, in which case barrier resistant doors are designed with the architectural style in mind. 
• As common practice, with regards to wiring distribution, Cobeal: 
  • Retains decorative millwork and other character-defining features. 
  • Avoids obscuring or altering decorative cornice and other character-defining features. 
  • Considers raceways hidden by historic cornices and moldings (for ornamental spaces). 
  • Does not install exposed wiring systems. 
  • Creates a maintenance plan with strict standards for the installation of new wiring and equipment, ensuring that copies of wiring diagrams are available to building managers. 
  • Designs for flexibility and expansion. 
  • Does not drill marble, parquet, terrazzo, and other finished flooring. If unavoidable, Cobeal drills in corners to minimize impacts, running wiring along baseboards. 
  • Selects high-quality, highest-speed, and smallest size cabling to minimize the need for future intrusive replacements, especially in ornamental significant spaces. 

Historic lighting levels may not be appropriate for current or planned use of a historic building and the installation of new lighting systems may be unnecessary. The lighting levels and equipment selected is appropriate to the building's current or planned use while respecting the original fabric. 

• With regards to interior lighting, Cobeal: 
  • Retains as much original fabric as possible when installing new systems (i.e., does not needlessly puncture a decorative plaster ceiling or molding, when it may be feasible to relocate a fixture or junction box).
  • Retrofits existing light fixtures with reflectors to increase light output.
  • Conserves and rewires existing fixtures and accessories. Even if original fixtures will not be electrified and/or used, Cobeal retains and preserves them in situ. 
  • When original fixtures cannot produce the amount of light required, Cobeal uses alternative light sources from removable fixtures, such as task lighting and torchéres. Inconspicuous sconces or unobtrusive perimeter ceiling lighting is preferred to eye-catching modern fixtures. 
  • Retains and reuses original, character-defining switch plates and other accessories. 
  • Uses existing electrical chases. Installs new chases within or behind walls or vertically in secondary or tertiary spaces. 
  • When using historically sensitive replacements that are wired for modern energy loads and light output, replicas of original lighting fixtures can be designed to accommodate energy efficiency and multiple light sources. 
  • Incorporates the original light color in new lighting plans. 
  • Ensures that the addition of interior lighting systems and other repairs will not corrupt the building's structural integrity. 
• With regards to exterior lighting, Cobeal: 
  • Considers landscape features when designing exterior lighting schemes; outside lighting will have implications on landscape design. 
  • Considers security and accessibility requirements. 
  • Mounts on existing poles or structures. 
  • Installs in non-intrusive areas. 
  • Uses accent lighting as an effective way to highlight architectural features. Uses gentle, raking light rather than large spotlights. Façades are not flooded with excessive light. 
  • When installing exterior lighting features, such as light poles or lower light sources, Cobeal works with your team to choose historically appropriate options. 
  • Ensures that the addition of exterior lighting systems and other repairs will not corrupt the building's structural integrity. 

Prior to initiating a plumbing upgrade, Cobeal works with your team to ascertain whether these traditionally utilitarian spaces are in fact historic and therefore must be preserved. If they are not historic, Cobeal rehabilitates them with sensitivity to the surrounding historic building materials, finishes, and features. When plumbing elements are historic, Cobeal takes care to preserve them, by: 

• Retaining and preserving historically significant configuration, layout, and plumbing elements, such as bathroom and kitchen fixtures and features. 
• When repairing/replacing existing pipes, Cobeal does not damage adjacent finish materials, such as floors and wall tiles. When new pipes must be installed and are visible, they are located inconspicuously. The design chosen compliments adjacent finishes. 
• Using existing pipe runs in their original location. Otherwise, Cobeal installs them in closets, service rooms, and wall cavities.
• Not cutting through character-defining features, such as moldings, wainscoting, etc. 
• Ensuring that the addition of plumbing systems and other repairs will not corrupt the building's structural integrity. 

Elevators and escalators may also contribute to a building's historic significance. Cobeal works with you to ascertain whether these features are historically significant, by: 

• Reusing existing components to the maximum extent possible. 
• Retaining original fixtures, features, and materials; many historically significant conveyance systems still retain some, if not all, their original elements, particularly finish elements. Examples are original, exotic wood veneers within elevator cabs and bronze and brass switch plates, floor indicators, and handrails. 
• Combining code requirements and preservation concerns; Cobeal may slightly modify original features to bring them up to code. 
• Ensuring that the addition of conveyance systems and other repairs will not corrupt the building's structural integrity. 

When Cobeal works with you to update your historical building's structure, we do our best to retain and repair as much of the original structural system as possible. When it is necessary to add an entirely new structural system or to strengthen the existing system with modern innovations, Cobeal carefully examines best practices to: 

• Develop creative solutions to meet life/fire safety requirements as well as historic preservation goals. 
• Ascertain whether the building's structure or structural components are integral to the character-defining features of the building, retaining as much of the original structural form and features as possible. 
• Plan a use for the building that doesn't necessitate an augmented structural system. 
• Consider the 'physics' of a proposed repair (i.e., will the alteration have the same thermal expansion coefficient as the existing structural system?).
• Carefully remove, catalogue, and store original adjacent features, finishes, and details for later re-installation. Sometimes it is necessary to remove existing finish materials and temporarily number the features to access the structural system. 
• Preserve extant features of historic structural systems, such as post and beam systems and trusses. 
• Sensitively reinforce structural systems; sister principal structural components rather than replace them. 
• Document any structural features that are too deteriorated to retain. 
• Replace missing or deteriorated materials in-kind; examples include replicating cast iron columns. When substitute materials are unavoidable, Cobeal aims to convey the same form, design, and overall visual appearance as the historic feature. These replications are documented. 
• Use reversible repair and maintenance methods, for instance, spray in urea-formaldehyde foam would be inappropriate for a historic structural system. 
• Ensure that the addition of building systems and other repairs will not corrupt the building's structural integrity.