Guidelines For Locating New Ducts, Grilles, Light Fixtures And Switches In Historic Buildings
- Procedure code:
- Prsrvtn Ntbk Series/Mech & Elec Systems For Historic Bldgs
- Basic Mechanical Requirements
- Last Modified:
GUIDELINES FOR LOCATING NEW DUCTS, GRILLES, LIGHT FIXTURES AND
SWITCHES IN HISTORIC BUILDINGS
This standard includes general guidelines for locating new
mechanical and/or electrical systems in historic buildings with
minimal adverse impact on the building's appearance or character.
When possible, install new systems that are reversible.
- Reuse existing holes where possible.
Use existing interstitial spaces to conceal systems.
- Conceal wiring when possible.
Conceal piping and ductwork as much as possible, but DO NOT
install suspended ceiling systems to do so.
- If suspended ceiling systems must be installed, DO NOT allow
system to abut glazing. The historic appearance of the window
should be maintained where possible. This can be accomplished
by "boxing" around window heads and leaving the complete
window exposed to view.
Where piping cannot be easily concealed by providing
alternative routes through less significant spaces, provide
gypsum board enclosures of the minimum size necessary to
sufficiently conceal the pipes.
- Preserve ornamental walls and ceilings as much as possible.
Avoid penetrating or attaching to ornamental finishes.
1. Where possible, place pipes, conduit, etc. along recessed
ledges or other areas of minimal visibility.
2. Where possible use piping of minimum diameter for
3. Paint pipes, conduit, etc. where possible to blend with
4. Where possible, use decoration patterns to disguise new
placement of wiring or systems.
Conceal ductwork in unused closets when possible and provide
- Use an air-sampling system instead of a smoke detector when
possible; only a small hole in the ceiling is required and
very little space in the ceiling is required for the pipe.
Conceal sprinkler heads and smoke detectors in decorative
- Use unused fireplaces for return air ducts.
Use permanently placed furniture to disguise ductwork.
- Reuse original hardware, such as grilles, etc. where possible.
Specify new grilles, light fixtures, etc. to match original as
closely as possible, in material and pattern.
- If reuse of an existing grille is not possible, leave original
grille in place and locate new grille within five feet of
original location - preferably on a non-ornamental surface
such as flat plaster.
CAUTION: FOR SOME SYSTEMS SUCH AS FIRE ALARM PULLS AND
BELLS/HORNS, FIRE SAFETY STANDARDS MAY PROHIBIT THE RETENTION
OF A DEFUNCT SYSTEM, AS THIS MAY CAUSE CONFUSION BETWEEN THE
ACTIVE AND INACTIVE SYSTEM DURING AND EMERGENCY.
Rewire, clean and refinish original fixtures when possible.
- NEVER attach fluorescent fixtures directly to ceiling
Conceal the light source when installing indirect lighting.
- Introduce as few new fixtures and holes in the ceiling as
Provide emergency lighting that is as unobtrusive as possible;
use a small fixture if possible; make sure the battery pack is
- Conceal ambient lighting behind ceiling moldings when
Conceal conduit for light switches, fire alarms and other
controls behind decorative surfaces if possible rather than
attaching it onto the surfaces.
- Paint switch plates and access panels separately so they can
be easily removed.
Conceal fire alarm equipment behind unused heating grilles.
- Use wireless fire alarm systems when possible to eliminate
unsightly conduit and wiring.
Conceal electrical panelboards in unused closets when possible
and provide adequate ventilation.
- Conceal smoke detectors in decorative plaster ceilings.
END OF SECTION