Design Guidelines For Installing Sprinkler Systems In Historic Buildings

PREFACE: This procedure includes general guidelines to follow when installing sprinkler systems in historic buildings. It identifies specific design issues and outlines recommended installation solutions that have the least visual or physical impact on the historic materials.

1. To the maximum extent possible, design sprinkler installations to be reversible, i.e. removable without sustaining major damage to historic finishes.
2. Conceal Piping:
   1. Conceal piping to significant spaces such as lobbies, corridors, and executive suites by routing pipes through adjoining office space. Use these pipes to feed sidewall heads in the significant spaces. DO NOT install suspended ceilings to conceal overhead piping.
      NOTE: USE THIS RULE OF THUMB FOR ALL RESTORATION ZONES
      IDENTIFIED IN THE BUILDING’S HISTORIC STRUCTURE REPORT (HSR). Check the HSR chapter entitled “Recommendations for Maintenance, Restoration, and Alteration” (usually Chapter 9) for building-specific design guidelines. HSR’s have been completed for most historic buildings in GSA’s National Capital Region inventory. A list of competed HSR’s and copies of each are available in the GSA-NCR Technical Resources Library, 7th and D Streets, SW, Washington, DC 202-708-6278.
   2. In contiguous significant spaces where no alternative route for concealing piping exists, install pipes in the space of lesser importance. Conceal piping in gypsum board enclosures of the minimum size needed to allow access for maintenance.
   3. Do not channel masonry walls to conceal piping. This alternative is costly and destructive.
3. Specify Sprinkler Heads Having the Least Physical and Visual Impact on Historic Materials and Design:
   1. Specify the smallest available pendant or sidewall sprinkler head. (For normal ceiling and wall sprinkler installations, Omega Commercial Extended Coverage Pendant Model EC-20 and Omega Commercial Extended Coverage Sidewall Model HEC-12 are recommended. See G.2., below, for guidance on selecting sprinkler heads for ornamental ceilings and exposed pipe installations).
   2. Recessed heads are not generally recommended because of the danger that they will become painted shut. Semi- recessed heads, despite the advantage of projecting less for installation in plaster ceilings. The holes created to accommodate these heads give ceilings a pockmarked appearance.
   3. As a rule, use sidewall heads in significant spaces with plaster walls. Use pendant heads in spaces that have both flat plaster ceilings and ornamental wall finishes (such as wood paneling or stone).
4. Match Sprinkler Heads to Original Finishes:
   1. Match heads and escutcheons to the dominant original metal in the area of the building where sprinklers are to be installed.
   2. Custom match heads and escutcheons to the historic paint color of the wall or ceiling in which they will be installed.
5. Detail Sprinkler Head Installations for Minimum Visibility: Specify the minimum possible sprinkler head projection from the wall or ceiling.
6. Detail Suspended Ceilings to Preserve Exterior Appearance of Windows:
   1. In standard office space and other areas approved for installation of suspended ceilings (consult HSR “Inventory of Significant Spaces” and “Recommendations”), hold back suspended ceilings from the window plane sufficiently to maintain the historic appearance of the window.
   2. Do not allow suspended ceilings to abut window glass. Keep back 3 feet and minimize difference of ceiling height to window height.
7. Preserve Ornamental Walls and Ceilings:
   1. Avoid penetrating ornamental finishes. Where neither walls nor ceilings are flat plaster, use the following guidelines:
      1. Place pipes on deep cornices and other ledges, exposed but not visibly noticeable.
      2. Use copper piping of minimum diameter needed to achieve required pressure.
      3. Paint pipes prior to placement to match adjoining finishes.
      4. Where unavoidably penetrating ornamental ceilings, distribute heads symmetrically and take advantage of decoration patterns to disguise heads. Camouflage heads in rosettes and other repeating motifs. Omit escutcheon plates. Specify glass bulb pendant heads.
   2. For exposed pipe installations and installations involving penetration of ornamental ceilings, specify glass bulb heads, such as Central GB-QR Glass Bulb Quick Response Pendant or GB-QR Glass Bulb Quick Response Sidewall heads. Glass bulb heads have the following advantages for these installations:
      1. Omission of escutcheon plates will not violate their UL listing.
      2. They are the smallest available head for this type of installation.
      3. The entire head, excluding the small heat-sensitive glass bulb activator, can be custom coated to match any finish. This coating must be done by the manufacturer (you supply the paint). For guidance on custom matching, see “Guidelines for Identifying Historic Paint Colors”.