Div 09

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BUILDING TECHNOLOGY I
Div 09 FINISHES
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1. CONCRETE SURFACE FINISHES
1.01 STUCCO OR CEMENT PLASTER FINISH

• Stucco is a mortar consisting of cement, sand and
  water. Hydrated lime is often added to make the
  mortar easier to work. It is applied in three
  coats
• scratch and brown coats are mixed in the
  proportion of
• 1 part Portland cement to 3 parts of sand,
  with about
• 10lbs. of hydrated lime.
• The finish coat is usually richer in the
  proportion of
• 1 part of Portland cement to 2 parts of sand.
• Coarse sand is used for the base coats and fine
  sand
• for the finish coat.
• Before applying for the stucco or cement
  plaster, the concrete (or masonry) surface should
  be roughened to ensure good bonding.
• Old concrete surfaces are roughened with a bush
  hammer or small pick, and then washed thoroughly
  with acid and water to remove all dirt and loose
  particles.
• New concrete can be roughened with a heavy wire
  brush or a special scoring tool.

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1. CONCRETE SURFACE FINISHES
1. CONCRETE SURFACE FINISHES
1.01 Stucco or Cement Plaster
1.01 STUCCO OR CEMENT PLASTER FINISH
1.02 Rubbed Finish
1.03 Brushed Finish
1.04 Tooled Finish
The scratch coat is then trowelled onto the wall
surface. Just as soon as the first coat is but
not hard, it is scratched with a small rake to
form a key for the second coat. Average
thickness of the scratch coat is 3/8. The
brown coat is applied a few days after the first
coat has set firm and hard, also to a thickness
of 3/8. It is applied with a wood float and
leveled to a flat, even and relatively smooth
surface. The finish coat is applied over the
brown coat after all work is free from waves and
cracks, and set and dry. Thickness of the finish
coat is 1/8 minimum and rarely exceeds ¼ except
for finishes requiring rough texture. The finish
coat should be kept damp but not wet for a few
days, to prevent hairline cracks.
1.05 Sand-blast Finish
1.06 Exposed Aggr
1.07 Wood Float Finish
1.08 Steel Trowelled
1.09 Integral Colored- Cement Finish
2. GRANOLITHIC FINISH
2.01 Granolithic
2.02 Terrazo
3. TILE FINISHES
3.01 Cement Tile
3.02 Ceramic Tile
3.03 Asphalt Tile
4. RESILIENT FLOOR FIN
4.01 Asphalt Tile/Sheet
4.02 Vinyl Tile/Sheet
4.04 Rubber Tile/Sheet
4.05 Linoleum Sheet
5. WOOD FLOOR FIN
5.01 StripFlooring
5.02 Plank Flooring
5.04 Parquet Tile Floor
6. CEILING FINISHES
6.01 Ceiling Board
6.02 Acoustic Tile
7. PAINT FINISHES
7.01 Transparent Fin
7.02 Opaque Fin
7.03 Paint Defects
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1. CONCRETE SURFACE FINISHES
1.02 RUBBED FINISH
This consist of grinding down the surface of the
concrete a day or two after it is poured, using a
brick of carborundum, emery or soft natural
stone. With the rubbing, which is done with a
circular motion, a thin grout of cement and sand
is applied to the surface and well rubbed in to
fill surface imperfections, and the work
afterward washed down with clean water. If fine
sand is used instead of a grout, the method is
called a sand-float finish .
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1. CONCRETE SURFACE FINISHES
1.03 BRUSHED FINISH
This type of finished is obtained by scrubbing or
brushing the concrete surface with fiber or wire
brushes and water to remove the surface film or
mortar, leaving the coarse aggregate exposed.
This should be done while the concrete surface
is still green and just as soon as it is possible
to do so without removing particles of the
aggregate. The appearance of a brushed finish
can be improved by washing with a diluted
solution of acid applied with a brush. The acid
thoroughly cleans the surface of the aggregate,
thereby intensifying the color and texture of the
same. The surface should be thoroughly washed
after the acid treatment as otherwise it will
have a mottled, streaky appearance.
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1. CONCRETE SURFACE FINISHES
1.04 TOOLED FINISH
Concrete surfaces may be finished by tooling by
any of the methods employed for dressing or
finishing natural stone. Bush hammering, either
by hand or by pneumatic tool, is the most popular
method used in tooling concrete surfaces. The
best results are obtained on surfaces which are
thoroughly hard. The concrete should preferably
be about 2 months old. Only small-sized
aggregate should be used in the facing material,
as it is hard to dress and obtain uniform results
where large angular stones are encountered.
Tooling cannot ordinarily be performed
satisfactorily on gravel concrete, as the pebbles
will be dislodged before being chipped.
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1. CONCRETE SURFACE FINISHES
1.05 SAND-BLAST FINISH
A sand-blast finish is very much the same in
appearance as that obtained by brushing the
concrete while it is still green. Sand blasting
produces a granulated finish somewhat similar to
sandstone but not so uniform, because the
aggregates are likely to be brought out
irregularly. The concrete should be thoroughly
hardened before sand-blasting. A clean, sharp,
thoroughly dried silica sand or crushed quartz is
most effective for sand-blasting. A 3/8noxxle
may be used, but under ordinary conditions ¼ or
even 1/8 have found to give good results. The
best results are obtained on a thoroughly
hardened concrete surface at least a month old,
and for such work a nozzle pressure of from 50 to
80 lbs. will be required.
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1. CONCRETE SURFACE FINISHES
1.06 EXPOSED AGGREGATE FINISH
The color is obtained from exposed aggregate and
not by adding coloring material to the
mixture. Facing mortar of I part Portland
cement, 1-1/2 parts sand, and 3 parts of special
screenings or pebbles of the desired color shall
be placed against the forms to a thickness of
about 1 inch sufficiently in advance of the body
concrete to prevent the latter from coming into
contact with the forms.
Such colored or other special aggregate used for
finish shall be exposed by scrubbing as in 1.03.
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1. CONCRETE SURFACE FINISHES
1.08 STEEL TROWELLED FINISH
After the concrete aggregate is forced below the
surface, the surface is leveled with a straight
wood screed, and given a wood float finish.
Before the concrete finally sets, the entire
surface is steel-trowelled
1.09 INTEGRAL COLORED-CEMENT FINISH
When the concrete is still green but surface
water is gone, the surface is leveled with a
straight wood screed. Then a finish coat of 13
mortar is applied. This finish coat is leveled
with a wood screed, given a wood float finish and
then steel-trowelled
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2. GRANOLITHIC and TERRAZO FLOOR FINISHES
2.01 GRANOLITHIC FINISH
This consists of a topping with a mixture of 1
part cement, 1 part sand and 1 part finely
crushed stone. It is called granolithic because
fine aggregate chips were originally used in the
aggregate. Finely ground corundum may also be a
part of the aggregate to produce an enduring and
non-slip surface .
2.02 TERRAZO FINISH
Terrazzo is a mixture of cement, marble chip
aggregates and water laid as a topping or as a
wall finish, and ground to a fine, smooth
surface. It is used for floor and bases where
durability, resistance to wear, and minimal
maintenance are necessary. It is available either
in precast form e.g. tile, or cast-in-place form,
with either a smoothly polished or non-slip
surface. For non-slip surfaces, abrasive
granules are added to the mixture.
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2. GRANOLITHIC and TERRAZO FLOOR FINISHES
2.02 TERRAZO FINISH
The terrazzo topping shall consist of 200 lbs. of
marble chip aggregate to 1 bag (94 lb.) of
cement. The matrix may either be white or gray
Portland cement as desired. For non-slip heavy
duty floors the mixture shall consist of 150 lbs.
of marble chip aggregate and 50 lbs. of abrasive
granules to one bag of cement.
Common specifications require that 70 of the
marble aggregate for terrazzo topping must show
- for heavy-duty non-slip topping a
proportion of three marble granules to one
abrasive must show and - for light-duty
non-slip topping, where the abrasive is
sprinkled on the finish, a proportion of four
marble to one abrasive granule must show.
Minimum thickness of terrazzo topping is 5/8.
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3. TILE FINISHES
3.01 CEMENT TILE FINISH
Cement tile is manufactured by pressing in moulds
a plastic mixture of cement and sand. Surface
color of the tile is achieved by the addition of
mineral oxide colors. Thickness of cement tile
is 25mm (1). Common sizes are squares 200mm x
200mm (8x8), 300mm x 300mm (12x12), and 400mm
x 400mm (16x16). When installing cement tile,
the top of the base slab shall be left 50mm (2)
below the finish floor. The tiles shall be
thoroughly soaked in water before laying on a
setting bed of cement mortar (1 part of Portland
cement to three parts of sand).
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3. TILE FINISHES
3.02 CERAMIC TILE FINISH
Ceramic tile are small surfacing units made from
clay or mixture of clay with other ceramic
materials and fired according various processes.
Tiles differ principally in (1) composition
of the body (2) surface finish, that is, glazed
or unglazed (3) process of manufacture and (4)
the degree of vitrification or fusion of the tile
body after firing, as indicated by the
extent to which it absorbs moisture
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3. TILE FINISHES
3.02 CERAMIC TILE FINISH

• Composition
• Tiles are made of compounded and of natural clay
  bodies. Those made of compound bodies contain
  three principal constituents
• the plastic, usually clays having high bonding
  power
• and some fluxing ability
• the filler which reduces shrinkage in drying
  and firing
• and imparts to the body a certain rigidity
  which
• prevents deformation under heat, e.g. flint or
  finely
• pulverized silica, kaolin, tale and
• the flux or solvent which melts under intense
  heat
• and fuses the heat resisting elements into a
  solid
• mass.
• The most widely used flux in floor and wall tiles
  is the
• minimal feldspar.

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3. TILE FINISHES
3.02 CERAMIC TILE FINISH
Finish Unglazed tiles are composed of the same
ingredients throughout and derive their color and
texture from the materials of which the body is
made. Glazed tiles have a glassy surface of
ceramic materials fused upon their face to give
them a decorative appearance and to make the
surface impervious to moisture.
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3. TILE FINISHES
3.02 CERAMIC TILE FINISH

• Glazes are produced in a large variety of colors,
  ranging from pure white to jet black. Glaze
  finishes are of two general classes in their
  light reflecting qualities
• bright glazes, which have a highly polished
  surface
• and reflect an image clearly and
• matte glazes, or those which do not clearly
  reflect an
• image or are entirely without sheen.
• All degrees of semilustrous or satinlike finish
  may be produced between the two extremes of
  reflection and nonreflection.
• In addition, glazes may have
• Plain
• textured
• polychrome
• mottled
• stippled or
• rippled surface

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3. TILE FINISHES
3.02 CERAMIC TILE FINISH

• Manufacture
• Dust-press Process. Dust-pressed tiles are shaped
  in steel dies by applying heavy pressure to the
  damp ceramic mix while it is in finely pulverized
  form. The dust-press method of production gives
  greater mechanical precision and a more regular
  appearance to the tiles than other methods.
• Plastic Process. Plastic-made tiles are shaped
  from clay rendered plastic by mixing with
  sufficient water. They are made either by hand
  molding or by extrusion from an auger-machine.
  When shaped by machine, the extruded ribbon of
  clay is cut into the desired sizes as it emerges
  from the die. Most types of tile made by the
  plastic method vary slightly from the true
  geometric forms and therefore have a more
  hand-made appearance than to dust-presseded
  tiles.

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3. TILE FINISHES
3.02 CERAMIC TILE FINISH

• Vitrification
• Vitrification is a measure of the tiles density
  and relative absorption which depends partly on
  the tiles composition and partly on the degree
  of burning. There are four degrees of
  vitrification
• Nonvitreous tiles have a degree of density that
  permits
• moisture absorption of more than 7 of the
  weight of
• the tile but does not prevent the tile from
  having a high
• degree of strength.
• Semivitreous tiles have a degree of density
  that limits
• moisture absorption to from 3 to 7 of the
  weight of
• the tile.
• Vitreous tiles have a moisture absorption of
  less than
• 3 and a body density which prevents any
  penetration
• of dirt that cannot be easily removed.
• Impervious tiles are the hardest. Their
  moisture
• absorption is negligible and they are readily
  cleansed
• of stains and dirt.

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3. TILE FINISHES
3.02 CERAMIC TILE FINISH

• Types of Ceramic Tiles
• Glazed interior tiles
• are non-vitreous product made by the
  dust-press-process .

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3. TILE FINISHES
3.02 CERAMIC TILE FINISH

1. Ceramic Mosaic Tiles

are tiles less than 6 sq. in. in facial area,
preponderantly unglazed, and having fully
vitrified or fairly dense bodies. To
facilitate installation, ceramic mosaic tiles are
usually mounted at the factory on sheets of paper
about 2 sq. ft. in area, individual tile units
being spaced so as to allow for the insertion of
cement between them when the paper is removed and
the face of the tiles is exposed .
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3. TILE FINISHES
3.02 CERAMIC TILE FINISH

• Quarry tiles
• are unglazed floor tiles made from natural clays
  or shales by the plastic method. They are a very
  durable flooring material, being impervious to
  moisture, stains and dirt, and are resistant to
  abrasion .
• Pavers
• are standard size unglazed tiles resembling
  ceramic mosaic tiles in composition and physical
  characteristics but usually having facial area of
  6 sq. in. or more. Because of their greater size,
  which usually ranges from 3x3 to 6x6, these
  tiles are generally not pasted onto paper but are
  laid out individually. When by the plastic
  method, it is either vitreous and semivitreous
  dust-pressed pavers are either impervious or
  vitreous. All pavers are weatherproof and are
  especially suitable for heavy floor service .

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4. RESILIENT FLOOR FINISHES
4.01 ASPHALT TILE SHEET FINISH

• Resilient flooring is manufactured as tile or
  sheet including
• Asphalt
• vinyl
• rubber
• linoleum, and
• cork.
• Vinyl, linoleum and rubber flooring are available
  also in sheet form .

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4. RESILIENT FLOOR FINISHES
4.01 ASPHALT TILE SHEET FINISH
This consists of thoroughly bonded composition of
thermoplastic binder (asphaltic type for standard
asphalt tile and resinous for greaseproof asphalt
tile), asbestos and other fibers, inert filler
materials (various stone dust, diatomite, mica,
etc.) and inert color pigments, formed under
pressure while hot and cut to size. Asphalt
tile is usually made in 9 squares and less
commonly in 12 squares. Rectangular
borders18x24 are made in a limited variety of
colors and patterns. Usual thickness are 1/8 and
3/16.
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4. RESILIENT FLOOR FINISHES
4.01 ASPHALT TILE SHEET FINISH
Asphalt tile may be installed on any smooth
concrete subfloor above or below grade and on any
wood subfloor with sufficient strength so that no
deflection can occur. In either case there
should be no dampness - It should not be
used out-of-doors or for interiors subject
to strong direct sunlight - on concrete
floors where dampness or hydrostatic
pressure exists - on any under floor that
is not smooth, even and clean (as the
flooring will reveal exactly the contours of the
under flooring surface) - in many
areas where water may be constantly
splashed on the floor, e.g. shower rooms and
toilet rooms and - in areas where
grease can accumulate unless greaseproof
asphalt tile is used.
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4. RESILIENT FLOOR FINISHES
4.02 VINYL TILE SHEET FINISH
Vinyl resilient flooring materials are divided
into three major types a. solid vinyl b.
vinyl and asbestos combined c. a thin vinyl
layer applied to other types of resilient
flooring materials .
Tiles Vinyl tiles (all vinyl) are made into the
ff thicknesses - 1.5mm - 2.0mm
- 2.5mm and - 3mm in squares 300mm x
300mm Sheet in rolls 2.0mm and 2.5mm thick x
1.80m (6) wide and in 50m lengths. The thicker
sheet is used in areas where heavy traffic will
be encountered.
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4. RESILIENT FLOOR FINISHES
4.02 VINYL TILE SHEET FINISH
Vinyl flooring is recommended where a colorful,
textured, tough, durable, easily maintained,
grease-resistant type of finish flooring is
required for areas of both light and heavy human
traffic. It may be used for above-grade,
on-grade and below-grade floors. Vinyl flooring
should not be used - for exterior floor
surfaces - in areas where specific chemicals
that attack vinyl are used
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4. RESILIENT FLOOR FINISHES
4.03 RUBBER TILE SHEET FINISH
Tiles Rubber floor tiles are as a rule made of
neutral rubber for greatest resilience. Sizes,
thicknesses, as well as methods of application
and precautions to follow in installation, are
much the same as for vinyl floor tiles
Sheet Rubber sheet flooring is manufactured in
rolls 3 wide, in thicknesses of 3/32, 1/8 and
3/16, with 3/32 most commonly used in home
installations. Rubber sheet flooring is applied
according to the general rules given for linoleum.
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4. RESILIENT FLOOR FINISHES
4.03 RUBBER TILE SHEET FINISH
Advantages of rubber flooring are - It is
the quietest floor possible with the exception of
thick cork tile - its color are
more brilliant than those of other types.
Rubber flooring, however, is not as resistant
to soap, oil and many household solvents, as
vinyl and linoleum
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4. RESILIENT FLOOR FINISHES
4.04 LINOLEUM TILE SHEET FINISH
Linoleum is resilient, waterproof floor covering
that consists of a backing covered with a
relatively thick layer of wearing surface. This
wearing surface is a mixture that contains
oxidized linseed oil processed in a special way,
combined with wood or cork flour, various
fillers, stone dust, whiting, diatomite), resins
binders, driers and inert color pigments.
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4. RESILIENT FLOOR FINISHES
4.04 LINOLEUM TILE SHEET FINISH
Linoleum can be divided into five
classifications - plain - marbled
- spatter - straight-line inlaid, -
molded inlaid.
It is available in three gauges - service
(1/16) - standard (3/32), and -
heavy (1/8).
It comes in rolls 2 and 6 wide and up to 30 ft.
in length, and in 9x9 tiles for plain and
marbled
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4. RESILIENT FLOOR FINISHES
4.04 LINOLEUM TILE SHEET FINISH
Linoleum is recommended in areas - where a
resilient, durable, colorful, greaseproof,
waterproof type of flooring is needed -
where there is spillage of water such as baths
and toilet rooms - where there is
spillage of grease, fruit juices, etc.
such as kitchens, cafeterias for countertops and
desk tops where heavy wear, grease and
cooking spillage occur. It should not be
used - on concrete slabs below grade and
subflooring where dampness can penetrate
from below - for exteriors - where any
strong alkalis and acids may be present. When
specifying linoleum, the latest colors, patterns,
and textures should always be checked because
many of these are quickly discontinued
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5. WOOD FLOOR FINISHES
5.01 STRIP FLOORING
This type of flooring consists of
tongue-and-grooved (TG) boards 6 or less in
width. Nominal sizes of strips are - 1 x 3,
1 x 4 and 1 x 6 - net (face) widths
are 2-1/4, 3-1/4, and 5-1/4
respectively. - Net thickness is 7/8.
In laying strip flooring, the strips are started
square the room against either side wall. The
first strip is placed with the grooved edge
towards the wall and shall be face-nailed as
close to the wall as possible so that the
baseboard will conceal the nailing. All
succeeding strips are blind-nailed. The strips
should be laid in such a manner that joints in
successive courses do not come together.
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5. WOOD FLOOR FINISHES
5.01 STRIP FLOORING
Strip flooring is often laid over a concrete slab
subfloor, nailed to 2x3 or 2x4 sleepers or
screeds embedded or anchored to the concrete
floor. The sleepers should be treated with a
suitable wood preservative. The space between
the finish floor and the top of the concrete slab
is filled with cinder concrete or other
damp-proof composition fill
In laying strip flooring, the strips are started
square with the room against a wall. The first
strip is placed with the grooved edge towards the
wall and shall be face-nailed as close to the
wall as possible so that the baseboard will
conceal the nailing. All succeeding strips are
blind-nailed. The strips should be laid in such a
manner that joints in successive courses do not
come together.
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5. WOOD FLOOR FINISHES
5.02 PLANK FLOORING
This type of flooring consists of square-edged
boards 8 or more in width as are commonly found
in old Spanish- period houses. Plank flooring
is usually faced-nailed.
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5. WOOD FLOOR FINISHES
5.03 PARQUET TILE FLOORING
Also called block flooring, consists of square
pieces or blocks which have been built up in
several layers like plywood and having a veneered
surface, or consists of several parquet strips
assembled at the factory to form a tile. This
type of flooring may also be nailed to a wood
subfloor or set in mastic to a concrete subfloor.
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5. WOOD FLOOR FINISHES
5.03 PARQUET TILE FLOORING
Tiles are 3/8 or 5/15 in thickness, in squares
of 9-5/8 x 9-5/8, 14-1/2 x 14-1/2, 19-1/4 x
19-1/4 and 24 x 24. For wooden subfloors,
lumber must be properly kiln-dried (or use 12mm
or 19mm plywood). An 11mm depression below the
finish floor level is necessary for 10mm thick
parquet tile flooring.
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5. WOOD FLOOR FINISHES
5.03 PARQUET TILE FLOORING
Concrete subfloors must be level and flat.
Freshly poured concrete should be allowed to
cure for at least two weeks before laying
parquet. Slab construction must be such that it
will stay dry. For concrete subfloors directly
over fill, the base of the surrounding slab
should be above ground level and/or finish grade.
It is desirable that the slab be constructed with
a vapor-moisture barrier (see PLASTICS).
Asphalt-type underlayment, felt paper, should
not be used.
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6. CEILING FINISHES
6.01 CEILING BOARD
These are shiplapped boards with a bead running
along the center of the board and along the
joint, hence it is often referred as beaded
ceiling board (B.C.B.) Thickness are 3/8 and ½
in. Widths of boards are 4 and 6 in.
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6. CEILING FINISHES
6.02 ACOUSTIC TILE
Acoustic tile is used for ceiling and wall
finishes in rooms where it is required to control
sound by absorption.
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6. CEILING FINISHES
6.02 ACOUSTIC TILE

• There are several types of acoustic tile
• Cellulose fiber tile.
• These are made from compressed sugar cane or
  wood fibers with perforations on the surface of
  the tile.
• Mineral wool tile.
• Felted rock wool with a fissured surface.
  Mineral wool tile has limited acoustic values, is
  flame retardant but will not withstand rough
  usage and cannot be painted. It is available in
  ½, 5/8, 2/4, 7/8 and 1 in. thickness. Sizes are
  12x12, 12x24 and 24x24.
• Glass fiber tile.
• These are made of glass fibers held together by
  binder. Thickness is 1-1/4. Sizes are 23-3/4 x
  23-3/4 or 47-3/4.

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7. PAINT FINISHES
7.01 TRANSPARENT FINISHES

1. Wood Stains

• Oil Wood Stains
• Pigments are derived from various earth clays.
  After they are dissolved in linseed oil, the
  coloring particles remain suspended between the
  oil molecules. For spreading the color particles
  over large surfaces, the ground oil color is
  thinned with turpentine .
• Water Stains
• These are made from anilyne dyes and mineral
  extracts which have been dissolved in hot water
  .
• Spirit or Alcohol Stain
• These are mixed with alcohol-solution anilyne
  powders and warmed alcohol.

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7. PAINT FINISHES
7.01 TRANSPARENT FINISHES

1. Wood Stains

The method of applying wood stains 1. Clean
wood surface by planing, scraping and sanding. 2.
If water stain is to be used, sponge wood with
damp rag and allow to dry. 3. Resand with finer
grit paper. 4. Fill holes, dents, cracks, etc.
with crack filler colored to match stains. When
dry, sand smooth. 5. Dust and clean with benzene
rags. 6. Apply stain, using brush or sponge with
grain. 7. Apply shellac wash coat 6 parts
alcohol to 1 part shellac. 8. Scuff surfaces
lightly with fine sandpaper by hand. 9. Apply
paste filler and wash off in 10 minutes. 10.
Sand, dust and clean. 11. Apply shellac wash
coat. 12. Sand, dust and clean. 13. Select any of
the ff. finishes a.) shellac and wax, b)
varnish, c.) lacquer
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7. PAINT FINISHES
7.01 TRANSPARENT FINISHES

1. Wood Fillers

• Paste Fillers.
• Composed of silex (stone dust), japan-drier,
  linseed
• oil, turpentine, and sometimes colors ground
  in oil
• Filler is applied with the grain and allowed
  to dry
• flat for about 10 minutes. It is then
  wiped off across
• the grain with burlap or some other coarse
  material.
• Paste fillers requires about 24 hours for
  drying
• before it can be sanded.
• Crack Fillers.
• Plastic wood putty, stick shellac, etc. They
  are used
• for filling nails holes, cracks and dents.

44
7. PAINT FINISHES
7.01 TRANSPARENT FINISHES

1. Shellac

Shellac is made by refining seed lac and its
natural color is orange white shellac is
obtained by bleaching. Lac is a resin exuded by
certain insects in India in the twigs of trees.
These twigs with the resin attached are called
sticklac and are crushed and washed to produce
seed lac.
Shellac is an under or a preparatory coat for
varnish and wax finishes, but is not satisfactory
as an indepen-dent finish because it is not
durable and turns white from contact with water.
It is also used to cover wood knots before a
priming lead and oil coat is applied because it
kills the resin in the knot and prevents
discoloration.
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7. PAINT FINISHES
7.01 TRANSPARENT FINISHES

1. Varnish

It is a resolution of resin in drying oil (oil
varnish) or in a voltatile solvent such as
alcohol or turpentine (spirit varnish). It
contains no pigment and hardens into a smooth,
hard and glossy coat by the oxidation of the oil
or by the evaporation of the alcohol. The chief
resins used in varnishes are - copal of
African fossil gums - dammar or resins from
Singapore and the East Indies - the residue
left under the extraction of turpentine from pine
resins, and rosin esters, obtained by treating
resin with glycerine to make it waterproof when
dry.
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7. PAINT FINISHES
7.01 TRANSPARENT FINISHES

1. Varnish

In general, oil varnishes are more durable than
spirit varnishes. Spirit varnishes are either
dammar varnish, mad by treating dammar resins
with turpentine, or shellac varnish, made by
dissolving white or orange shellac in grain
alcohol. They dry by the evaporation of the
solvent.
Drying time is from 4 to 24 hours. Varnish
should never be applied when the weather is moist
or humid.
47
7. PAINT FINISHES
7.01 TRANSPARENT FINISHES

1. Lacquer

Lacquer is made synthetically, and is closely
related to rayon or nylon fabrics. It requires a
special thinner sold by each manufacturer for his
own brand. Average drying time is 1-1/2 hours.
For fine lacquer finishes, a special undercoat of
lacquer sealer is applied over a wash coat of
shellac. After the sealer has dried, it is
sanded or steel-wooled to give the lacquer a
gripping surface
48
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

Paint is a mixture containing a pigment and a
vehicle. The pigment is that solid, finely
ground portion which gives to paint the power to
obscure, hide or color the surface. The vehicle
is the fluid portion of the paint. It carries the
particles of the pigment in suspension and by the
oxidation deposits and hardening binds them to
painted surface or by evaporation deposits them
thereon.
49
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

• PIGMENTS
• may be divided into white and colored pigments.
  The white pigments can, in turn, be divided
  further into hiding or active pigments and
  extender pigments.
• Hiding or active pigments

are those which when mixed with the drying
oil, produces an opaque finishing material.
The most widely used active pigment is white
lead which, when used alone withlinseed
oil, will produce an excellent durable
paint. Other active white pigments include
- zinc oxide - lithopone -
titanium dioxide.
50
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

• Extender pigments
• are inert pigments which when mixed with the
  drying
• oils possess very little hiding power.
• They are often referred to as fillers,
  extenders or
• suspenders. They serve to prevent the primary
  
• pigment from settling in a hard mass at the
  bottom of
• the paint can.
• The extender pigments include
• - calcium carbonate
• - silica and
• - mica.

51
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

• Extender pigments
• All paints other than white paints also
  contain color
• pigments in addition to white pigments.
• A good exterior paint should contain not less
  than
• 65 pigment by weight.
• High quality exterior paints contain not more
  than
• 10 of extender pigments

52
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

• VEHICLE
• The vehicle or liquid portion of the paint
  consists of
• - a binder which forms the film
• - the drier to speed up formulation of the
  film and
• - the thinner or the volatile solvent .
• The volatile solvent facilitates application
  and
• contributes, through its evaporation, to the
  drying of
• the paint, but is not a permanent part of
  the film.
• The type of solvent used in a paint
  determines
• whether it is a
• - water-base paint (where the solvent is
  water) or
• - oil-base paint (where the solvent is an
• organic liquid).
• The vehicle of a paint should not contain
  more than
• 35 of the paints volume by weight .

53
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

• The principal paint for exterior wood surfaces is
  oil paint, which contains white lead as the white
  paint pigment, color pigments and extenders in a
  vehicle consisting of a drying oil, usually
  linseed oil, dryers, and turpentine as the
  solvent or thinner.
• Other drying oils used are
• tung or china oil,
• soybean and
• fish oils.
• Driers are added to the vehicle of paints
  containing drying oils to accelerate the
  hardening of paint by speeding the union of the
  oil with oxygen from the air.
• A good paints vehicle will contain 85 to 95
  drying oil and the rest thinners and driers.

54
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

Driers may be classified into two types -
oil driers, used in powdered or crystalline
form such as litharge (monoxide of
lead), manganese dioxide, borate and
- liquid driers, inorganic compounds of lead,
manganese and cobalt, which are
dissolved in turpentine or benzene and
which mix readily with the oil at
ordinary temperatures.
55
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

Thinners act as a solvent both for the
materials of the paint and for the resin in the
wood surface thereby providing greater
penetration and anchorage in the wood pores. It
improves the brushing and spreading qualities of
the paint and also hastens its drying by
absorbing oxygen from the air and transferring it
to the drying oil. The best thinner is
turpentine, a spirit obtained by steam
distillation of the resin or gum which exudes
from pine trees. (The residue of the distillation
is known as rosin, used in the making of
varnish.) Other thinners include mineral spirits
(petroleum distillation products) benzol, solvent
naptha.
56
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

Thinners Turpentine is also added to the first
or priming coat to assist the penetration of the
paint and in much smaller quantities to the outer
coats especially for exterior work. Because it
dries without a gloss, it is mixed with the final
coats for interior finishes when a flat or dull
finish is required.
57
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

Alkyd-resin or oil-resin emulsion paints where
oil and resin emulsified in water makes a
heterogeneous finishing material by an
emulsifying agent such as casein. A great
advantage of oil resin paint is that its
viscosity can be easily reduced by the addition
of water. Water is added as a thinner for the
same reason that turpentine or mineral spirits is
added to oil paints. Other advantages of
oil-resin emulsion paints are that it dries
quickly (two coats can be applied the same day)
it is easy to apply it is easy to recoat with
itself or other paint, and it has little tendency
to fade.
58
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

Synthetic latex (rubber-base) paints is made
from synthetic latex which acts as the pigment
binder and the film-forming material for the
paint. A careful balance of synthetic latex and
alkyds resins gives a solution that can thinned
with water for application as a continuous film
with excellent adhesion and wash ability.
Synthetic latex paints have little tendency to
turn yellow because, unlike oil paints, they
absorb very little oxygen from the air. Latex
paint is the preferred paint for the plaster,
cement, concrete and masonry
59
7. PAINT FINISHES
7.02 OPAQUE FINISHES

1. Paint

Portland cement-base paints a water-base paint
(where the solvent is water) used for painting
concrete and masonry surfaces
Enamel paints paints which use varnish as a
vehicle. They have the ability of levelling brush
marks, are more resistant to washing and rough
usage, and have a harder and tougher film. They
can have either a glossy, semi glossy or matt
finish.
Rust-inhibiting paints protective paints for
ferrous metal and are of two types - priming
paint, e.g. red lead, litharge, lead chromate -
finish paints, e.g., lead sulfate and zinc dust.
60
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS
Well-formulated paint, skillfully applied over a
properly prepared surface wears by gradual
chalking and maintains a smooth, tough and
durable film that constitutes a satisfactory
surface for repainting. Such a paint film will
remain an effective protective coating for a
period of three to five years depending upon the
locality and the characteristics of the original
surface. It requires little treatment beyond
surface dusting in preparation for
repainting. Defective paint behavior and surface
failures, on the other hand, are traceable to
three main causes 1. Improper paint
formulation. 2. Inadequate surface preparation
and careless application. 3. Faulty
construction or building materials
61
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS
Film defects may result from one or any
combination of these. The following are the
various paint defects, their causes, prevention

1. Excessive or premature chalking

• evidenced by surface dusting and rapid thinning
  of the film, sometimes to bare wood.
• caused by improper formulation or paint
  application.
• too high a percentage of volatile thinner forms a
  porous film subject has completely worn away.

62
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Excessive or premature chalking

• too high a percentage of volatile thinner forms a
  porous film subject has completely worn away.

• May be prevented by strict adherence to high
  standards of paint formulation and application.

63
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Sagging and running

• marked by irregular wavy lines that texture an
  otherwise smooth finish film.
• cause is usually paint formulation with too low a
  pigment volume, or too heavy and careless an
  application of a thin-consistency paint. It
  occurs sometimes when repainting an interior if
  an original gloss surface has not been cut by
  light sanding.
• Cure of condition necessitates sanding the
  irregularities and repainting. Prevention
  involves maintaining proper proportions of
  pigment and linseed oil as to formulation and
  careful brushing of properly thinned paint as to
  application

64
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Storm spotting

• usually occurring after continuous rains and
  electric storms, are characterized by unsightly
  and irregular color changes.
• Rain sometimes absorbs nitrates and peroxides
  formed by electrical discharges and penetrates
  the paint film, changing the refractive index of
  the coating.

• Cure of condition can sometimes be accomplished
  by rubbing spots with alcohol. Subsequent
  weathering usually restores the original color
  within a month or two.

65
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Washing

• is characterized by streaking on the surface,
  fading color, the final exposure of the original
  surface and accumulation of pigment particles
  below the painted area.
• caused by water-soluble compounds in pigments of
  poor paints or soluble compounds which develop by
  chemical reactions in the paint are dissolved
  during rain storms and wash out of the film.
• also when paints are applied during periods of
  high humidity and low temperatures, the film
  structure may be injured during the drying
  period.

66
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Stains

• are surface discolorations which often disappear
  gradually as the paint film wears. Sometimes,
  however, they go through the film necessitating
  its removal and subsequent repainting.
• Metal stains are sometimes caused by water
  dripping from exposed metal.
• Prevention involves coating metal. Galvanized
  iron should be painted with metallic zinc dust in
  spar varnish or paint containing zinc oxide.

67
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Stains

• Mildew stains are caused by air-borne fungi that
  feed on oil and multiply rapidly. They cannot be
  easily removed. Old growth should be removed
  before repainting by washing with 1 lb. of
  tri-sodium phosphate or sodium carbonate in 1
  gallon of water.
• For prevention, the paint can be treated with
  about 1/4 oz. of mercuric chloride per gallon.

68
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Checking

• characterized by minute cracks on the surface of
  elastic paint films. Usually it is not a serious
  film defect, for checks do not extend through the
  film.
• cause is improper application or improper
  formulation of undercoats. The finish film is
  applied over a body coat not quite enough for a
  proper foundation. Unequal tensions occur in
  drying and small surface checks result.
• cure of condition involves wire brushing affected
  areas and repainting if checking does not
  disappear under influence of normal wear.
• prevention involves allowance of sufficient
  drying time between coats and formulation of the
  body coat with a minimum amount of oil in order
  to develop a hard foundation for finish

69
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Alligatoring

• an advance state of checking, varying in degree
  to a coarse texturing of the finish film.
• cause involves application of a harder drying
  finish over soft or slow-drying under-coats. As
  in checking, poor formulation with too much
  linseed oil in the priming or body coat may
  result in alligatoring.
• cure of condition, if extensive, requires removal
  of the film and repainting.
• prevention necessitates precautions noted above
  to prevent checking

70
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Cracking and scaling

• characterized by irregular cracks that
  subsequently curl at the edge, flake and finally
  scale off. Over wood, scaling is usually most
  marked in direction of or across the grain.
• cracking is a wear characteristic of hard-drying
  paints that contain large proportions of zinc
  oxide pigment.
• scaling comes from the water pressure when
  moisture seeps through the crack to the original
  surface. The condition is common to any surface
  coated with paint improperly formulated to
  withstand local conditions.

71
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Cracking and scaling

• cure of condition at an early stage requires
  vigorous brushing and recoating with a less
  brittle film.
• prevention involves formulation to produce a
  tougher, more elastic film. Usually this means an
  increased percentage of white lead.

72
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Blistering and Peeling

• characterized by swelling of the entire film
  which is usually followed by a break in the film
  and subsequent peeling.
• cause is water pressure from behind the film due
  to faulty construction that allows moisture
  seepage or abnormal condensation. This is a
  mechanical damage that may occur whatever the
  type or quality of paint used.

• sometimes also results also when damp surfaces
  are covered by quick-drying paints.
• This type of damage may be evident on wood,
  stucco or masonry surfaces .

73
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Blistering and Peeling

• cure of condition requires complete removal of
  the paint and repainting as for new work.
• prevention necessitates permanent removal of the
  moisture sources, often involving extensive
  repairs and waterproofing.

74
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Spot fading

characterized by color changes and flatting of
gloss in irregular patches on the film. cause
is from uneven oil absorption, usually a result
of insufficient coats or a priming coat
improperly formulated to penetrate and adequately
seal surface pores. It may be emphasized when
skimping is attempted, that is, application of
two coats when three are needed, or the use of a
cheaply formulated paint. cure of condition is
repainting. prevention requires merely the
exercise of proper painting technique.
75
7. PAINT FINISHES
7.03 PAINT BEHAVIOR AND DEFECTS

1. Wrinkling

not to be confused with alligatoring, is marked
by a tough, leather-like texturing. cause is
usually when paint is put on too thickly and not
well brushed out and may be contributed to by
formulation if too high a proportion of oil is
used in finish coats. cure of condition
requires only sanding and repainting if texture
is slight. Otherwise, film removal is indicated
with subsequent painting as for new work .
prevention requires strict adherence to high
standards of paint formulation and thorough
brushing out in application
76
End of Div 09 FINISHES