Historic Preservation - Technical Procedures
Stripping And Repainting Exterior Galvanized Metal Windows
National Capitol Region Specifications - Icc Building
Doors And Windows
Stripping And Repainting Exterior Galvanized Metal Windows
STRIPPING AND REPAINTING EXTERIOR GALVANIZED METAL WINDOWS
A. This procedure includes guidance on removing paint build-
up and repainting of all exterior galvanized metal
windows to return them to operable condition. It also
includes caulking all joints between metal elements and
masonry where required.
B. Safety Precautions: All precautions shall be taken to
prevent the possibility of fire in storage space and
areas being painted.
1. Provide adequate ventilation for removal of toxic
2. Provide at least one 2B fire extinguisher for each
200 square feet of area occupied for paint storage
C. 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).
1.02 QUALITY ASSURANCE
A. Standards: National Association of Corrosion Engineers,
5.1.3 NACE No. 3 Commercial Blast Cleaned Surface Finish
in "Visual Standards for Surfaces of New Steel Ariblast
Cleaned and Sand Abrasive."
1.03 DELIVERY, STORAGE AND HANDLING
A. Packing and Shipping: Deliver materials to the site in
the manufacturer's original containers with labels
showing manufacturer, contents and color. Delivered
material shall be identical to accepted literature and
B. Storage and Protection: Store all materials in a single
ventilated space. Storage space shall be kept neat and
clean. Used rags, waste, and empty containers must be
removed from the site at the end of each work day.
1.04 PROJECT/SITE CONDITIONS
A. Environmental Requirements:
1. The temperature of the surface to be painted and of
the air in contact therewith shall be maintained at
a minimum of 50 F and maximum of 95 F.
2. No painting shall be done when relative humidity
3. Surfaces to be painted shall be protected from dust
and dirt during painting and finishing.
A. The Sherwin Williams Co.
101 Prospect Ave, N.W.
Cleveland, OH 44101
B. Devcon Corporation
30 Endicott Street
Danvers, MA 01923
A. Paint for Exterior Steel:
1. Primer: One coat of zinc dust-zinc oxide primer
such as "Galvanized Iron Primer," (Sherwin
Williams), or approved equal; minimum 2 mil.
D.F.T. (Dry Film Thickness) total.
2. Finish Coats (2): Alkyd gloss such as "Matalastic
II Enamel," (Sherwin Williams), or approved equal;
minimum 4 mil. D.F.T. (Dry Film Thickness) total
for both coats.
1. Primer: Make each coat clearly different in color.
2. Base and Finish: Alkyd resin semi-gloss: Benjamin
Moore or Sherwin Williams; make colors clearly
different from each other and primer.
3. Dry Film Thickness: Apply materials at not less
than manufacturer's recommended spreading rate, to
establish a total dry film thickness as indicated
for each coat.
a. Primer: 2 mils.
b. Base and Finish Coats: 2 mils each.
C. Dry Grit Blasting: Fine grit No. 2-3 at 80-100 psi.
D. Backer Rod: Polyethylene compressible rod 50% larger in
diameter than joint.
1. Multi-part, non-sag urethane sealant in conformance
with ASTM C290, Type M, Grade NS, Class 25 light
buff to match color of window paint.
2. Joint primer recommended by the sealant
manufacturer for specific applications and
F. Fillers: Two-part epoxy metal filler, putty grade such as
"Plastic Steel A" (Devcon Corporation), or approved
A. Wire Brush: Non-ferrous metal brush, such as brass.
A. Protection: Enclose dry grit blasting work areas with
temporary scaffolding or framework sufficient to support
tarpaulin enclosure to prevent escape of abrasive. Shield
adjacent masonry and glass with a temporary covering of
cardboard or fiberboard held in place with heavy-duty
strapping tape or wood bracing.
B. Surface Preparation:
1. Determine that surfaces to which paint is to be
applied are even, smooth, sound, clean, dry and
free from defects affecting proper application.
Contact the Contracting Officer after surfaces to
be repainted have been cleaned and made smooth and
before any paint is applied.
2. Remove all paint, rust and scale from all steel
surfaces, especially undersides and hidden
locations by mechanical and manual methods as
necessary. Do not remove or damage any of the
galvanized surface. Stop abrasive blasting as soon
as foreign matter and paint has been removed. The
sash are to be restored to full operation.
3. Paint removal may be done by dry grit blasting,
scraping or sanding.
4. Remove all window air conditioning units from
5. Remove all sealant between metal window frames and
6. Clean the bare metal of all oily or greasy residue
with a degreaser such as trichlorethylene available
commercially in standard metal degreasers.
7. Fill all small holes, depressions and cracks with
metal filler following manufacturer's written
directions. Finish all filled areas by sanding
flush, after curing time has elapsed. Prime all
metal within two hours of cleaning down to bare
metal using a color obviously different from the
3.02 ERECTION, INSTALLATION, APPLICATION
A. Apply paint in accordance with manufacturer's printed
B. Apply paint evenly and smoothly, free of runs, drips,
sags, crawling, brush marks, holidays and clogging or
angles. All paint coatings shall be brush or roller
applied as appropriate to surface and finish.
C. Apply successive coats only when preceding coats are
thoroughly dry and hard. Sand between coats to produce
even and smooth surfaces.
D. Apply additional coats when undercoats, stains, or other
conditions show through final coat of paint, until pain
film is of uniform finish, color and appearance. Ensure
that corners, edges, crevices and exposed fasteners
receive a dry film thickness equal to that of flat
E. Meeting lines between colors shall be straight and
sharply defined with no blending, running or gaps.
F. Adjacent materials shall be fully protected by drop
cloths or other suitable coverings. Paint drips,
splatters, etc., shall be removed immediately.
G. Each coat of paint is to be slightly darker than the
preceding coat with the final coat exactly matching the
END OF SECTION