Architectural Plans and Specifications
The execution of plans and specifications for preservation projects is more complex than for construction of a new building. The reasons for this include:
- The existing materials in a historic building were rarely subject to the quality control standards found in today’s manufacturing processes.
- Often archaic materials are present, that is to say, materials seldom used in the same way today. These materials present special challenges in their repair or replacement. For example, acquiring sod to repair a historic soddy involved more than specifying material type, we had to source the sod and observe while it was cut from New Mexico’s Rio Grande Valley by Pueblo Indians.
- “Techniques for Repairs” must be fully articulated, particularly as they relate to workmanship. A repair of historic double-hung wood windows requires a specification with 38 separately described steps.
- Several alternative procedures for repairs may need to be specified to provide the contractor with a choice to provide an alternate with the most comfort for them. An example of this might be providing multiple alternate jacking procedures for structural stabilization. Contractor comfort is increased, and consequently the potential for costs reduction is enhanced.
- The retention of historic materials requires more care than its wholesale replacement. When a roof leaks, it is more often than not changed out (wholesale) rather than fixed (piecemeal). To create repair specifications takes more skill and effort than to create total replacement specifications. For example, the repair of a marble interior floor might require different repair techniques for chips, cracks, and gloss recovery.
The knowledge required to create appropriate plans and specifications for historic preservation is different than that required for new architecture, and firms must keep abreast of and evaluate emerging products and techniques, as well as research and learn historic methods and materials. Firms must be diligent in “keeping up.”
Construction period services are more intense than is typical for new construction. Fostering respect for the building, decisions about what is too deteriorated to save, or whether a historic wall will hold together; collaborative discussion with the general contractor and/or tradesman about alternatives; these are all decisions requiring more job site time.