Replacing Joint Sealants Between Architectural Bronze Window Frames And Exterior Stone Masonry
- Procedure code:
- National Capitol Region Specifications - State Department
- Thermal And Moisture Protection
- Joint Sealers
- Last Modified:
REPLACING JOINT SEALANTS BETWEEN ARCHITECTURAL BRONZE WINDOW FRAMES
AND EXTERIOR STONE MASONRY
A. This procedure includes guidance on replacing damaged or
deteriorated joint sealants between heads, jambs, and
sills of architectural bronze window frames and exterior
B. Architectural Bronze is an alloy of copper, commonly
composed of approximately 57% copper (Cu), 40% zinc (Zn)
and 3% lead (Pb); it is actually a "leaded brass".
C. For general information on the characteristics, uses and
problems associated with bronze (including architectural
bronze, see 05010-03-R.
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. American Society for Testing and Materials (ASTM), 100
Barr Drive, West Conshohocken, PA 19428, (610) 832-9585
or FAX (610) 832-9555.
1.03 SYSTEM DESCRIPTION
A. System Performances: Provide joint sealers that have been
produced and installed to establish and maintain
watertight and airtight continuous seals.
A. Product date from manufacturers for each joint sealer
product required, including instructions for joint
preparation and joint sealer application.
B. Samples of Initial Selection Purposes: Submit three (3)
samples of the following items:
1. Caulking compound; after Contracting Officer's
Representative selection from manufacturer's color
chart, submit three (3) tubes.
2. Pre-molded filler; submit three (3) segments, 12"
C. Certificates from manufacturers of joint sealers
attesting that their products comply with specification
requirements and are suitable for the use indicated.
D. Qualification data complying with requirements specified
in Quality Assurance article. Include list of completed
projects with project name, names of Architects and
Owners, addresses and telephone numbers.
E. Sample Mock-Ups for Verification Purposes: Prior to
installation of joint sealers, apply elastomeric sealants
to each type of joint (3' minimum length) for further
verification of colors selected from sample submittals
and to represent completed work for qualities of
appearance, materials, and application. Locate mock-ups
as directed by Contracting Officer.
1.05 QUALITY ASSURANCE
A. Installer Qualifications: Engage an installer who has
successfully completed within the last 5 years at least
3 joint sealer applications similar in type and size to
that of this project.
B. Single Source Responsibility for Joint Sealer Materials:
Obtain joint sealer materials from a single manufacturer
for each different product required.
C. Preconstruction Compatibility and Adhesion Testing: Use
test methods standard with manufacturer to determine if
priming and other specific joint preparation techniques
are required to obtain rapid, optimum adhesion of joint
sealers to joint substrates. Perform tests under normal
environmental conditions that will exist during actual
1.06 DELIVERY, STORAGE AND HANDLING
A. Packing and Shipping: Deliver materials to project site
in original unopened containers or bundles with labels
informing about manufacturer, product name and
designation, color, expiration period for use, pot life,
curing time and mixing instructions for multi component
B. Storage and Protection: Store and handle materials to
prevent their deterioration or damage due to moisture,
temperature changes, contaminants, or other causes.
1.06 PROJECT/SITE CONDITIONS
A. Environmental Requirements: Do not proceed with
installation of joint sealers when ambient and substrate
temperature conditions are outside the limits permitted
by joint sealer manufacturer or below 40 F or when joint
substrates are wet due to rain, frost, condensation, or
A. All work under this section shall be guaranteed for not
less than five (5) years from the date of final
acceptance by the Government against leaks and weather
A. Dow Corning Corporation
1225 Northmeadow Parkway, Ste. 104
Roswell, GA 30076
P.O. Box 994
Midland, MI 48686-0994
B. General Electric Co.
Waterford, NY 12188
C. Pecora Corporation
165 Wambold Road
Harleysville, PA 19438
800/522-1285 or 215/723-6051
2601 Oakland Avenue
Garland, TX 75041
800/523-6688 or 214/278-8158
D. Tremco, Inc.
3735 Green Rd.
Beachwood, OH 44122
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 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. Compatibility: Provide joint sealers, joint fillers
and other related materials that are compatible
with one another and with joint substrates under
conditions of service and application, as
demonstrated by testing and field experience.
2. Colors: Provide color of exposed joint sealers
indicated or, if otherwise indicated, as selected
by the Contracting Officer from manufacturer's
B. Silicone Sealant: One-part silicone-based, nonsag,
elastomeric sealant, complying with ASTM C920, Type S,
Class 25, Grade NS, such as "Dow Corning 790" (Dow
Corning Corp.), "Silpruf SCS2000 Sealant" (General
Electric Co.), or approved equal.
C. Polyurethane Sealant: One-part polyurethane-based
sealant; complying with ASTM C920, Type S, Class 25. Use
self-leveling type for joints of floors and pavements,
such as "Dynatrol 1" (Pecora Corp.), "Dymonic" (Tremco,
Inc.), or approved equal.
D. Miscellaneous Sealant Materials:
1. Joint Primer/Sealer: Provide type recommended by
sealant manufacturer for joint surfaces to be
primed or sealed.
2. Bond Breaker Tape: Provide plastic tape as
recommended by sealant manufacturer for sealant-
contact surfaces where bond must be avoided for
proper performance of sealant. Provide self-
adhesive tape where applicable.
a. Any of three toxic, flammable, oily, isomeric,
aromatic hydrocarbons that are di-methyl
homologues of benzene and are obtained from
wood tar, coal tar, or petroleum distillates;
Also a mixture of xylenes and ethyl-benzene
used chiefly as a solvent.
b. Other chemical or common names include Xylene
(C8H10); P-xylene; 1,4-dimethyl benzene.
c. Potential Hazards: TOXIC AND FLAMMABLE.
d. Available from chemical supply house, hardware
store, paint store or printer's supply
a. A petroleum distillate that is used especially
as a paint or varnish thinner.
b. Other chemical or common names include Benzine*(not Benzene); Mineral spirits; Petroleum
spirits*; Solvent naphtha*.
c. Potential Hazards: TOXIC AND FLAMMABLE.
d. Safety Precautions:
1) AVOID REPEATED OR PROLONGED SKIN CONTACT.
2) ALWAYS wear rubber gloves when handling
3) If any chemical is splashed onto the
skin, wash immediately with soap and
e. Available from construction specialties
distributor, hardware store, paint store, or
printer's supply distributor.
4. Clean, potable water.
5. Clean, soft cloths.
A. Caulking gun
B. Wire brushes (non-ferrous bristles)
C. Tooling stick or knife
A. Surface Preparation:
1. All openings, joints, or channels to be sealed
shall be thoroughly clean, dry and free from dust,
oil, grease, loose mortar or any other foreign
2. Masonry surfaces forming sides of joints shall be
wire-brushed with non-ferrous brush, then air-blown
3. Prime or seal joint surfaces where recommended by
sealant manufacturer. Confine primer/sealer to
areas of sealant bond only.
4. Set joint fillers without twists, and to allow for
bond breakers, backer rods and sealants. Do not
leave gaps between ends of joint filler units.
5. Install sealant backer rod for sealants, except
where recommended to be omitted by sealant
6. Install bond breaker tape where required by
manufacturer's recommendations to ensure that
sealants will perform as intended.
3.02 ERECTION, INSTALLATION, APPLICATION
A. Caulking shall be gun-applied through a nozzle opening of
such a diameter so that the full bead of sealant is
gunned into the joint, filling the joint completely
without gaps or air pockets. A superficial or skin bead
will not be acceptable.
B. All beads shall be tooled immediately after application
to ensure firm, full contact with the inner faces of the
joints. Excess material shall be struck off with a
tooling stick or knife, dipped in solvent to avoid
tearing or stripping of the bead.
C. The finished bead shall be flush with the surface, or as
otherwise indicated by the Contracting Officer's
D. Provide two weep holes at window lintels, 1'-0" in from
E. Install sealants to depths as recommended by sealant
manufacturer to provide uniform shapes which allow
optimum sealant movement capability.
F. Do not allow sealants to spill onto adjoining work.
Adjacent surfaces which have been soiled by sealing
operations shall be cleaned immediately and left in a
clean and neat condition.
A. Excess compound shall be cleaned off non-porous surfaces
while uncured, using a solvent such as commercial xylol
or naptha. On porous surfaces, the excess sealant should
be allowed to cure and be removed by non-abrasive
mechanical means approved by the Contracting Officer's
B. Remove all rubbish, cartons and debris resulting from
caulking operations daily during the performance of the
END OF SECTION