MIL-HDBK-1110
recommendations for surface preparation procedures and standards
for specific substrates; recommendations for coating removal; and
general background information on surface preparation methods.
Surface preparation methods are summarized in Table 6.
6.2
Repair of Surfaces. All surfaces should be in good
condition before recoating. If repairs are not made prior to
painting, premature failure of the new paint is likely. Rotten
wood, broken siding, and other deteriorated substrates must be
replaced or repaired prior to maintenance painting. Water-
associated problems, such as deteriorated roofs and
nonfunctioning drainage systems, must be repaired prior to
coating. Interior moist spaces, such as bathrooms and showers
must be properly vented. Cracks, holes, and other defects should
also be repaired.
Areas in need of repair can sometimes be identified by
their association with localized paint failures. For example,
localized peeling paint confined to a wall external to a bathroom
may be due to inadequate venting of the bathroom. Refer to
Section 11 for more examples.
6.2.1
Joints, Cracks, Holes, or Other Surface Defects.
Caulks and sealants are used to fill joints and cracks in wood,
metal and, in some cases, in concrete and masonry. Putty is used
to fill holes in wood. Glazing is used to cushion glass in
window sashes. Specially formulated Portland cement materials
are available for use in cracks and over spalled areas in
concrete. Some of these contain organic polymers to improve
adhesion and flexibility. Other materials are available to
repair large areas of interior plaster (patching plaster), to
repair cracks and small holes in wallboard (spackle), to fill
joints between wallboards (joint cement), and to repair mortar.
Before application of these repair materials, surfaces should be
clean, dry, free of loose material, and primed according to the
written instructions of the material manufacturer.
Caulking and sealant compounds are resin based viscous
materials. These compounds tend to dry on the surface but stay
soft and tacky underneath. Sealants have application properties
similar to caulking materials but tend to be more flexible and
have greater extendibility than caulks. Sealants are often
considered to be more durable than caulks and may also be more
expensive. Commonly available generic types of caulks and
sealants include oil-based, butyl rubber, acrylic latex,
silicone, polysulfide, and polyurethane. The oil-based and
butyl-rubber types are continually oxidized by exposure to
sunlight and become brittle on aging. Thus, their service life is
limited. Acrylic-latex and silicone caulks tend to be more
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