Historic Preservation - Technical Procedures
Repairing Brass Window And Door Finish Hardware
Hspg Prepared For Nps - Sero
Doors And Windows
Repairing Brass Window And Door Finish Hardware
REPAIRING BRASS WINDOW AND DOOR FINISH HARDWARE
A. This procedure includes guidance on repairing brass
window and door hardware where these are deteriorated
(rusted and corroded) and where there are missing
elements. For guidance on cleaning brass hardware, see
05010-03-P and 08700-02-R.
B. Safety Precautions:
1. All workers must be protected from the effects of
chemicals during the cleaning/repairing operations.
2. Some chemicals suggested for brass maintenance are
flammable, toxic, or both. As a general rule,
avoid skin contact and inhalation of any chemical.
Rubber or plastic gloves should be worn when
handling hazardous (flammable or toxic) chemicals.
Follow storage and handling procedures printed on
the container labels of the cleaning solutions,
provide good ventilation while working, and
thoroughly wash hands after completion of the work.
3. Workers should take precautions to prevent epoxies
and their components from contacting the skin.
Provide protective clothing which must be worn and
protective creams for exposed skin areas.
Accidental contact with unprotected skin to these
materials must be treated immediately by washing
with soap and water, never with solvents. Exercise
care to avoid skin contact to tool cleaning
solvents and to provide adequate ventilation for
C. Historic Structures Precautions:
1. As with all other historic fabric, brass will have
a historic importance which must be identified at
an early stage. The item's merit, in terms of age,
uniqueness of design, materials, size,
technological development, association with persons
or events, exceptional workmanship or design
qualities, must be understood before decisions
regarding repair, maintenance and preservation can
2. Remove existing brass hardware components without
damage to the material itself, adjacent materials,
or substrate. Carefully label as to location.
Clean and reinstall carefully.
3. When choosing the brass hardware to be replaced,
the RHPO should be consulted to provide information
about how to match for color and type of the metal.
D. See 01100-07-S for general project guidelines to be
reviewed along with this procedure. These guidelines
cover the following sections:
1. Safety Precautions
2. Historic Structures Precautions
4. Quality Assurance
5. Delivery, Storage and Handling
6. Project/Site Conditions
7. Sequencing and Scheduling
8. General Protection (Surface and Surrounding)
These guidelines should be reviewed prior to performing
this procedure and should be followed, when applicable,
along with recommendations from the Regional Historic
Preservation Officer (RHPO).
A. Brass is an alloy resulting from the mixture of copper
and zinc. The color of brass varies, depending upon the
amount of zinc in the mixture and whether or not other
metals are added. Brasses with relatively large amounts
of zinc are yellow in color. The addition of aluminum
makes a light golden color. A small percentage of
manganese produces a bronze-like color. The addition of
nickel results in a silvery metal called nickel silver.
B. Brass is a hard, durable, and utilitarian metal, making
excellent castings. It can be worked hot, and extruded.
A very workable brass can be made by adding a little
lead. The process of extrusion is most commonly used,
especially to produce large architectural pieces,
including doors and elevators, and in such elements as
window frame sections, hand rails, and balustrades.
Brass was also used for architectural members because of
its corrosion resistance.
C. In colonial America, public buildings and fine homes
often had brass hinges, door knobs, door knockers,
chandeliers, and fireplace and irons; however, almost all
of the brass hardware was imported from England and
America, brass was used for light fixtures, plumbing
fixtures, and every type of builder's hardware. Polished
brass was a favorite for commercial buildings handrails,
stair railings, elevators, lobby furniture, building
1.03 SYSTEM DESCRIPTION
A. The natural beauty of the brass should be well preserved.
The hardware should be intact, in good condition, without
any signs of deterioration (corrosion by the action of
the atmosphere and acids derived from organic growths,
scaling, pitting, or severe rust). There should be no
missing elements. They should be securely mounted, and
properly set in the window or door frame, and there
should not be evidence of movement if it is pushed. Any
paint on brass must be continuous to be effective - it
should not be peeled exposing the bare metal.
1.04 DELIVERY, STORAGE, AND HANDLING
A. Packing and Shipping: For replaceable material: protect
brass hardware from damage at all times during handling,
installation, and operation of the building.
B. Acceptance at Site:
1. New metal parts shall be delivered on the job
carefully packed. Inspect each piece immediately
before installation, and do not use the pieces
which have observable surface damage.
2. Manufacturer's delivery or job markings on the
brass, and adhesives for manufacturer's labels,
shall either be a neutral or slightly acidic
material. In no case shall such material be
alkaline; any staining of the metal by alkaline
materials will cause for the rejection of the
C. Storage and Protection:
1. Brass hardware should be stored as to protect from
surface damage at all times, carefully packed and
should remain so from the time of delivery until
set. Keep uninstalled metal components in a dry,
rust-free storage facility.
2. Salvaged historic material shall be carefully
packed and stored under cover and in the building
away from working or traffic areas. Mark salvaged
material with the year of removal.
1.05 SEQUENCING AND SCHEDULING
A. Preventive Maintenance and Repair activities should be
scheduled during appropriate environmental conditions to
avoid weather related failures.
B. When cyclical maintenance work requires the use of high
ladders and other access equipment, perform as many work
items as possible.
NOTE: Chemical products are sometimes sold under a common
name. This usually means that the substance is not as pure as
the same chemical sold under its chemical name. The grade of
purity of common name substances, however, is usually adequate
for cleaning and stain removal work, and these products should
be purchased when available, as they tend to be less
expensive. Common names are indicated below by an asterisk
1. Butt hinges complete with all necessary screws
2. Mortise locks and latches complete with lock body,
rose, spindle, knobs, key plate, latch and strike
including all necessary screws and fastenings
3. Sash lifts and locks complete with all necessary
4. Sash counterweights complete with track, pulley,
cord and weight and all necessary screws
5. Metal thresholds complete with all necessary
6. Spring brass weatherstripping, 1 1/8" x .008", with
hemmed edges complete with screws or springs
7. Replacement screws and bolts
B. Emery paper, sandpaper (useful for smaller jobs or final
feathering of high paint edges, corners, or hard to reach
places), or fine steel wool.
C. Mineral spirits:
1. A petroleum distillate that is used especially as a
paint or varnish thinner.
2. Other chemical or common names include Benzine* (not
Benzene); Naphtha*; Petroleum spirits*; Solvent
3. Potential Hazards: TOXIC AND FLAMMABLE.
4. Safety Precautions:
a. AVOID REPEATED OR PROLONGED SKIN CONTACT.
b. ALWAYS wear rubber gloves when handling
c. If any chemical is splashed onto the skin,
wash immediately with soap and water.
d. Available from construction specialties
distributor, hardware store, paint store, or
printer's supply distributor.
A. Wiping cloths
B. Eye and skin protection
C. Gloves and protective gear
E. Putty knife
G. Wire brush
I. Electric drill
J. Electric wire brush
A. Determine the cause and extent of the problem. Determine
the age of the hardware and examine the condition of the
entire surface. Inspect for:
1. Wear - especially moving parts.
2. Parts - which have failed or which are unsecured,
broken, cracked, missing, distorted, or loose
(check screws and bolts).
3. Paint - coating failures such as chips, peeling,
checks, bubbling, and wear.
4. Rust corrosion - caused by moisture, deicing salts,
acids, soils, gypsum plasters, magnesium
oxychloride cements, ashes, clinkers, and sulfur
compounds. Determine the source of the moisture
which causes the deterioration.
5. Determine if the brass hardware can be salvaged.
6. Measure and record the dimensions of the various
metal parts needing replacement.
1. Protect all surrounding areas and surfaces during
application of rinsing solutions and against the
spread of dust, debris, and water.
2. All methods of enclosure and protection should be
approved by the supervisor. Protection should
consist of non-staining plastic sheets, tarpaulins
or burlap, secured to prevent lifting in high
B. Surface Preparation:
1. Good surface preparation is essential for good
adhesion of a protective coating following the
cleaning/repairing operations. To achieve this the
protective coating must be applied to a firm,
stable foundation which is free of contaminants
such as grease and water soluble salts.
2. Degreasing: Remove oil or grease to avoid
subsequent preparation methods spreading the
contamination over a wider surface. Wash the
features using warm water and detergent followed by
thorough water rinsing. Non-caustic degreasing
agents are also available or just wipe the surfaces
with white mineral spirits using a succession of
clean cotton swabs.
3.03 ERECTION, INSTALLATION, APPLICATION
A. Repair Due to Corrosion: Brass, like copper, is corroded
by exposure to moisture, acidity caused by polluted air
or newly-cut wood, chlorides, acetates, and ammonia.
Excrement from birds or other animals is acidic and can
also damage brass.
1. Lightly corroded areas due to moisture and/or
standing pools of water, where the brass has not
thinned, can be wiped and dried. If traces of rust
are visible, remove first with sandpaper then
clean, dry completely, and apply a protective
coating. For guidance in cleaning tarnished brass,
see 05010-32-R. For guidance in applying a clear
protective coating to brass features, see 05010-08-
P. For additional guidance in cleaning brass
features, see 05010-03-P and 05010-10-P.
2. Perforated spots and thinned surrounding areas can
be soft soldered with a patch large enough, and cut
appropriately, to cover the entire area.
3. See also 08700-02-R for guidance on cleaning door
B. For guidance on repairing dents, scratches, holes, nicks
and other minor imperfections, see 05010-02-R.
C. Missing pieces: Missing pieces can be reproduced by
casting. See 08700-01-R for guidance on replicating
D. Deterioration of Protective Coating:
1. Corrosion usually begins at breaks in the surface
and then spreads beneath it.
2. Completely remove protective coating from the
damaged elements and also any rust, using the
appropriate tools listed in the 'materials'
section. For guidance in removing paint or lacquer
from brass features, see 05010-31-R. For guidance
in reapplying a clear protective coating to brass
features, see 05010-08-P.
E. For repair work specific to sash weights and chains, see
08760-01-R. For repair work specific to hinges, see
08712-01-R and 08712-02-R.
F. Installation of hardware:
1. Check function of hardware against job site
conditions and interferences. Adjustments and/or
substitutions shall be made only as authorized.
2. Application shall be by skilled workmen, working
with proper equipment and shall fit the work of
others accurately, shall be applied securely and
adjusted properly. Exercise care not to damage
END OF SECTION