BT: FINISHING: PAINTS & COATING

PAINTS

is the solution of a pigment in water, oil or organic solvent, used to cove wood or metal articles either for protection or for appearance.

Architectural Paints

PAINT CLASSIFICATIONS

air-drying materials applied by brush or spray to architectural and structural surfaces and forms for decorative and protective purposes

Commercial Paints

PAINT CLASSIFICATIONS

air-drying or baking-cured materials applied by brush, spray, or magnetic agglomeration to kitchen and laundry appliances, automobile, machinery, furniture and used as highway marking materials

Industrial Paints

PAINT CLASSIFICATIONS

used as corrosion-resistant coatings and high temperature coatings

Pigment

PAINT COMPOSITION

gives the paint a color, but also plays a role in the consistency, ease of application, drying ability, durability, and hardness

Vehicle

PAINT COMPOSITION

a liquid in which pigment is dispersed before being applied to a surface to control consistency, adhesion, gloss and durability

Binder

PAINT COMPOSITION

makes the coat of paint retain its structure and bonds it to the surface to which it is applied

Solvent

PAINT COMPOSITION

dissolves the paint to make it usable and workable at normal room temperatures

Primer

TYPES OF PAINT

are basecoats applied to a surface to improve the adhesion of subsequent coats of paint or varnish

Sealer

TYPES OF PAINT

are basecoats applied to a surface to reduce absorption of subsequent coats of paint or varnish or to prevent bleeding through the finish coat

Oil Paints

TYPES OF PAINT

utilize a drying oil that oxidizes and hardens to form a tough elastic film when exposed to thin layer of air

Alkyd Paints

TYPES OF PAINT

have alkyd resin as a binder, such as chemically modified soy or linseed oil

Latex Paints

TYPES OF PAINT

a binder and acrylic resin that coalesces as water evaporates from the emulsion

Epoxy Paints

TYPES OF PAINT

have an epoxy resin as a binder for increased resistance to corrosion, abrasion, and chemicals

Rust inhibiting and Primers

TYPES OF PAINT

especially formulated with anti-corrosive pigments to prevent or reduce the corrosion of metal surfaces

Fire-retardant Paints

TYPES OF PAINT

especially formulated with silicone and polyvinyl chloride or other substance to reduce the spread of flame of a combustible material

Heat-Resistant Paints

TYPES OF PAINT

especially formulated with silicone resins to withstand high temperatures

Intumescent Coatings

TYPES OF PAINT

swells to form a thick insulating layer of inert foam when exposed to heat or fire that retards flame spread and combustion

paint
adhesion

putty

SURFACE PREPARATION

1. Previously painted surfaces

1.1. Scrape off loose ______ and sand smooth.

1.2. Remove old and fading paint to provide ——-

for the new coats of paint.

1.3. Nail back any loose boards and counter sink the nail head and fill with ———.

rough

primed

Putty

Caulk

SURFACE PREPARATION

2. New wood exteriors

2.1. Surface must be clean and dry.

2.2. Sand ——- spots.

2.3. All new wood surfaces must be ——-.

2.4. —— and fill all holes and cracks after the prime coat has been dried.

2.5. ——- joints around door and window frames.

plaster

SURFACE PREPARATION

3. Interior surfaces

3.1. Surfaces must be clean and free of wax, dirt and grease.

3.2. Repair with patching —— all cracks and holes.

3.3. Spot prime patched areas

3.4. Sand old surfaces

paint thinner

wire brushing / sand blasting

SURFACE PREPARATION

4. Metal surfaces

4.1. All surfaces must be clean and dry. Remove oil and grease with ——- or mineral spirits.

4.2. Remove any rust or loose paint by ——- or ——-. Bare spots on shop-coated steel and spot prime

Blistering

PAINT DEFECTS: INTERIOR

bubbles resulting from localized loss of adhesion and lifting of paint film from the underlying surface.

Blisters

PAINT DEFECTS: INTERIOR

Possible causes

• Applying oil-based or alkyd paint over a damp or wet surface

• Moisture seeping into the home through the exterior walls

• Exposure of the latex paint film to high humidity or moisture shortly after paint has dried, especially if there were inadequate surfaces.

1.2. Solutions

• If it does not go all the way down to the

  substrate: Remove by scraping and sanding and repaint with a quality acrylic latex interior paint.

• If it goes down to the substrate: Remove the source of moisture, if possible.

Blocking

PAINT DEFECTS: INTERIOR

undesirable sticking together of two painted surfaces when pressed together (e.g. a door sticking to the door jamb)

Blocking

PAINT DEFECTS: INTERIOR

Possible Causes

• Not allowing sufficient dry time for the coating before closing doors or windows.

Solutions

• Use top quality semi-gloss or gloss acrylic latex paint. Acrylic latex paints generally have better early block resistance that vinyl latex paints, or alkyd or oil- based paints.

Burnishing

PAINT DEFECTS: INTERIOR

increase in gloss or sheen of paint film when subjected to rubbing, scrubbing, or having an object brush against it.

Burnishing

PAINT DEFECTS: INTERIOR

Possible Causes

• Use of flat paint in highly trafficked areas, where a higher sheen level would be desired.

• Frequent washing and spot cleaning.

• Friction of objects against finish (e.g. furniture rubbing against the walls)

Solutions

• Paint heavy wear areas that require regular cleaning \e.g., doors, window sills and trim) with a top quality latex paint.

• In high traffic areas, choose a semi- gloss or gloss rather than a flat sheen level

Cracking/Flaking

PAINT DEFECTS: INTERIOR

splitting through at least one coat as a result of aging, which ultimately will lead to complete failure of the paint. In Its early stages, the problem appears as hairline cracks; In Its later stages,flaking occurs.

Cracking/Flaking

PAINT DEFECTS: INTERIOR

Possible Causes

• Use of a lower quality paint that has inadequate adhesion and flexibility.

• Over-thinning or overspreading the paint.

• Inadequate surface preparation, or applying the paint to bare wood without first applying a primer.

Solutions

• Remove loose and flaking paint with a scraper or wire brush, sanding the surface and feathering the edges.

• Prime bare wood areas before repainting.

• Use of a top quality primer and top coat should prevent a recurrence of the problem.

Foaming/Cratering

PAINT DEFECTS: INTERIOR

formation of bubbles (foaming) and resulting small, round concave depressions (cratering) when bubbles break in a paint film, during paint application and drying.

Foaming/Cratering

PAINT DEFECTS: INTERIOR

Possible Causes

• Shaking a partially filled can of paint.

• Use of low quality paint od very old latex paint.

• Applying (especially rolling)paint too rapidly.

• Excessive rolling or brushing of paint.

• Applying a gloss or semi-gloss pain over a porous surface.

Solutions

• Use high quality paints which allow good flow and appearance.

• Avoid excessive rolling or brushing of the paint or using paint that is more than a year old.

• Apply an appropriate sealer or primer before using such paint over a porous surface.

• Problem areas should be sanded before repainting.

Lapping

PAINT DEFECTS: INTERIOR

appearance of a denser color or increased gloss where wet and dry layers overlap during paint Application.

Lapping

PAINT DEFECTS: INTERIOR

Possible Causes

• Failure to maintain a “wet edge” when painting.

• Use of low solids “economy” paint.

Solutions

• Maintain a wet edge when painting by applying paint toward the unpainted area and then back into the just painted surface.

• This technique will produce a smooth, uniform appearance.

• It is also wise to work in manageable size areas; plan for interruptions at a natural break, such as window, door or corner.

• Using a top quality acrylic latex paint makes it easier to avoid lapping problems because high solids (pigments and binder) content makes lapped areas less noticeable.

• Alkyd paints generally have superior wet edge properties.

Mildew

PAINT DEFECTS: INTERIOR

black, grey or brown spots or areas on the surface of paint or caulk

Mildew

PAINT DEFECTS: INTERIOR

Possible Causes

• Forms most often on areas that tend to be damp, or receive little or no direct sunlight, such as, bathrooms, kitchens, laundry rooms and the like.

• Use of an alkyd or oil-based paint, or lower quality latex paint.

• Failure to prime wood surface before applying the paint.

• Painting over a substrate/coating on which mildew has not been removed.

Solutions

• Test for mildew by applying a few drops of household bleach to the area: if it is bleached away, the discolorant is probably mildew.

• Remove all mildew from the surface by scrubbing with a diluted household bleach solution (1 part bleach, 3 parts water), then rinse thoroughly.

• Use a top quality latex paint, and clean when necessary with bleach/detergent solution.

• Consider installing an exhaust fan in high moisture areas.

Mud Cracking

PAINT DEFECTS: INTERIOR

 deep, irregular crack resembling dried mud in a dry paint film

Mud Cracking

PAINT DEFECTS: INTERIOR

Possible Causes

• Paint is applied too thickly, usually over a porous surface.

• Paint is allowed to build up in corners upon application.

Solutions

• Remove coating by scraping and sanding.

• Prime and repaint, using a top quality latex paint.

• Mud-cracked areas can also be repaired by sanding the surface smooth before repainting with a top quality latex paint.

• Quality paints have a higher solids content, which reduces the tendency to mud crack. They also have a very good application and hiding properties, which maximize the tendency to apply a thick coat of paint

Sagging

PAINT DEFECTS: INTERIOR

downward “drooping” movement of the paint film immediately after application, resulting in a uneven coating.

Sagging

PAINT DEFECTS: INTERIOR

Possible Causes

• Application of a heavy coat of paint.

• Application in excessively humid and/or cool conditions.

• Airless spraying with the gun too close to the substrate being painted.

Solutions

• If paint is still wet, immediately brush out or re-roll to redistribute the excess evenly.

• If the paint has dried, sand and reapply a new coat of top quality paint.

• Correct any unfavorable conditions: do not thin the paint; avoid cool or humid conditions; sand glossy surfaces.

• Paint should be applied at its recommended spread rate rather than one heavy coat, which may lead to sagging.

• Consider removing doors to paint them supported Horizontally.

Surfactant Leaching

PAINT DEFECTS: INTERIOR

concentration of water-soluble ingredients on the surface of a latex paint, typically on a ceiling surface in rooms that have high humidity (e.g. shower, bathroom, kitchen); may be evident as tan or drown spots or areas, and can sometimes be glossy, soapy or sticky.

Surfactant Leaching

PAINT DEFECTS: INTERIOR

Possible Causes

• All latex paint formulas will exhibit this tendency to some extent if applied in areas that become humid especially in ceiling areas.

Solutions

• Wash the affected area with soap and water, then rinse.

• Problem may occur once or twice again before leachable material is completely removed.

• When paint is applied in a bathroom, it is helpful to dry it thoroughly before using the shower.

• Remove all staining before repainting.

Wrinkling

PAINT DEFECTS: INTERIOR

 a rough, crinkled paint surface, which occurs when uncured paint forms a “skin.”

Wrinkling

PAINT DEFECTS: INTERIOR

Possible causes

• Paint applied too thickly (more likely when using alkyd or oil-based paints).

• Painting during extremely hot weather or cool damp weather, which causes the paint film to dry faster on top than on the bottom.

• Exposure of uncured paint to high humidity levels.

• Applying top coat of paint to insufficiently cured primer.

• Painting over contaminated surface (e.g., dirt or wax)

Solution

• Scrape or sand substrate to remove wrinkled coating.

• If using a primer, allow it to dry completely before applying top coat.

• Applying an even coat of top quality interior paint.

Poor print resistance

PAINT DEFECTS: INTERIOR

tendency of paint film to take on the imprint of an object that is placed on it (e.g., a shelf, table, window sill or countertop with. books, dishes and other objects of them).

Poor print resistance

PAINT DEFECTS: INTERIOR

Possible causes

• Use of low quality semi-gloss or gloss paint.

• Putting a painted surface back into use before paint has fully dried.

Solution

• Use of top quality acrylic semi-gloss or gloss latex paint.

• Low quality latex semi-gloss and gloss paints can have poor print resistance, especially in warm damp conditions.

• Acrylic latex paints generally have better print resistance than vinyl latex paints.

• Fully cured alkyd paints also have excellent print resistance, Make sure the recommended “cure” time is allowed for the paint before it is put into service. Cool or humid conditions require more curing time.

Alligatoring

PAINT DEFECTS: EXTERIOR

patterned cracking in the surface of the paint film resembling the regular scales of an alligator.

Alligatoring

PAINT DEFECTS: EXTERIOR

Possible causes

• Application of an extremely hard, rigid coating, like an alkyd enamel, over a more flexible coating, like a latex primer.

• Application of a top coat before the undercoat is dry.

• Natural aging of oil-based paints as temperatures fluctuate.

• The constant expansion and contraction results in a loss of paint film elasticity.

Solution

• Old paint should be completely removed by scraping and sanding the surface; a heat gun can be used to speed work on large surfaces, but take care to avoid igniting paint/substrate.

• The surface should be primed with a high quality latex or oil-based primer, then painted w/ a top quality exterior latex paint.

Chalking

PAINT DEFECTS: EXTERIOR

formation of fine powder on the surface of the paint film during weathering, which can cause color fading. Although some degree of chalking is a normal, desirable way for a paint film to wear, excessive film erosion can result in heavy chalking.

Chalking

PAINT DEFECTS: EXTERIOR

Possible causes

• Use of a low-grade, highly pigmented paint.

• Use of an interior paint for an outdoor application.

Solution

• First remove as much of the chalk residue as possible, using a stiff bristle brush (or wire brush on masonry) and then rinse thoroughly with a garden hose; or use power washing equipment.

• Check for any remaining chalk by running a hand ewer the surface after it dries.

• If noticeable chalk is still present, apply a quality oil-based or acrylic latex primer (or comparable sealer for masonry), then repaint with a quality exterior coating; if little or no chalk remains and the old paint is sound, no priming is necessary.

Dirt Pickup

PAINT DEFECTS: EXTERIOR

 accumulation of dirt, dust particles and/or other debris on the paint film; may resemble mildew

Dirt Pickup

PAINT DEFECTS: EXTERIOR

Possible causes

• Use of low quality paint, especially lower grades of satin/semi-gloss

• Soil splashing onto siding.

• Air pollution, car exhaust and flying dust collecting on house body and horizontal trim.

Solution

• Wash off all surface dirt before priming and painting.

• If unsure whether the problem is dirt/mildew, conduct a simple spot test.

• Clean off dirt with a scrub brush and detergent solution, followed by a thorough rinsing with a garden hose.

• While dirt pickup can’t be eliminated entirely, top quality exterior latex paints typically offer superior

• dirt pickup resistance & washability.

• Also, higher gloss paints are more resistant to dirt pickup than flat paints, which are more porous and can more easily entrap dirt

Efflorescence/Mottling

PAINT DEFECTS: EXTERIOR

crusty, white salt deposits, leached from mortar or masonry as water passes through it.

Efflorescence/Mottling

PAINT DEFECTS: EXTERIOR

Possible causes

• Failure to adequately prepare surface by removing all previous efflorescence.

• Excess moisture escaping through the exterior masonry walls from the Inside.

Solution

• Eliminate the source of excessive moisture by repairing the roof, cleaning out gutters & downspouts, & sealing cracks in the masonry.

• If moist air is originating inside the building, consider installing vents/exhaust fans, especially in kitchen, bathroom & laundry areas.

• Remove the efflorescence & all loose material w/ a wire brush; then thoroughly rinse the surface.

• Apply a quality water-based or solvent-based masonry sealer and allow it to dry completely; then apply a coat of top quality exterior paint or elastomeric wall covering.

Frosting

PAINT DEFECTS: EXTERIOR

a white, salt-like substance on the paint surface. Frosting can occur on any paint color, but it is less noticeable on white paint or light tints. Onmasonry, it can be mistakes for efflorescence

Frosting

PAINT DEFECTS: EXTERIOR

Possible causes

• Forms mostly in protected areas (such as under eaves and on open porch ceilings) that do not receive the cleansing action of rain, dew and other moisture.

• Application of a dark-colored paint over a paint or primer containing calcium carbonate extender.

Solution

• Remove frosting by wire brushing masonry/sanding wood surfaces; rinse, then apply an alkyd-based primer before adding a coat of high quality exterior paint

Paint incompatibility

PAINT DEFECTS: EXTERIOR

loss of adhesion where many old coats of alkyd or oil-based paint received a latex top Coat.

Paint incompatibility

PAINT DEFECTS: EXTERIOR

Possible causes

• Use of water-based latex paint over more than three or four coats of old alkyd or oil-based paint may cause the old paint to “lift off” the substrate.

Solution

• Repaint using another coat of alkyd or oil-based paint or completely remove the existing paint and prepare the surface-cleaning, sanding and spot-priming where necessary before repainting with a top latex exterior paint.

Peeling

PAINT DEFECTS: EXTERIOR

loss of paint due to poor adhesion.

Peeling

PAINT DEFECTS: EXTERIOR

Possible causes

• Seepage of moisture through unsealed joints, worn caulk or leaks in roof or walls.

• Excess moisture escaping through the exterior walls.

• Inadequate surface preparation.

• Use of lower quality paint.

• Applying an oil-based paint over wet surface.

• Earlier blistering of paint.

Solution

• Try to identify and eliminate cause of moisture.

• Prepare surface by removing all loose paint with scraper or wire brush, sand rough surfaces, prime barewood.

• Repaint with a top quality acrylic latex exterior paint for best adhesion and water resistance.

Poor alkali resistance

PAINT DEFECTS: EXTERIOR

color loss and overall determination of paint film on fresh masonry.

Poor alkali resistance

PAINT DEFECTS: EXTERIOR

Possible causes

• Oil-based paint or vinyl acrylic latex paint was applied to new masonry that has not cured for a full year.

• Fresh masonry is likely to contain lime, which is very alkaline. Until the lime has a chance to react with carbon dioxide from the air, the alkalinity of the masonry remains so high that it can attack the integrity of all paint film.

Solution

• Allow masonry surfaces to cure for at least 30 days, and ideally for a full year, before painting.

• If this is not possible, the painter should apply a quality, alkali-resistant sealer or latex primer, followed by a top quality 100 percent acrylic latex exterior paint.

• The acrylic binder in these paints resist alkali attack.

Poor galvanized metal adhesion

PAINT DEFECTS: EXTERIOR

paint that has lost its adhesion to a galvanized metal substrate.

Poor galvanized metal adhesion

PAINT DEFECTS: EXTERIOR

Possible causes

• Improper surface preparation, such as inadequate rust removal.

• Failure to apply a primer before application of an oil-based or vinyl latex paint.

• Failure to sand baked-on enamel finishes or glossy surfaces before painting.

Solution

• Any rust on the metal should be removed with a wire brush; then an acrylic latex corrosion-resistant primer should be applied before applying an oil-based or vinyl latex top coat.

Poor gloss retention

PAINT DEFECTS: EXTERIOR

deterioration of the paint film, resulting in excessive or rapid loss of luster of the top coat.

Poor gloss retention

PAINT DEFECTS: EXTERIOR

Possible causes

• Use of an interior paint outdoors.

• Use of lower quality paint. Use of a gloss alkyd/oil-based paint in areas of direct sunlight.

Solution

• Direct sunshine can degrade the binder and pigment of a paint, causing it to chalk and lose its gloss,

• Surface preparation for a coating showing poor gloss retention should be similar to that used in chalking surfaces.

Vinyl siding warp

PAINT DEFECTS: EXTERIOR

warping or buckling of vinyl siding panels that have been repainted.

Vinyl siding warp

PAINT DEFECTS: EXTERIOR

Possible causes

• Most likely cause is that vinyl siding was painted with a darker color paint than the original color.

Solution

• Paint vinyl siding in a shade no darker than the original. Whites, off whites, pastels and other very light colors are good choices.

• Top quality acrylic latex paint is the best type of paint to use on vinyl siding, because the superior flexibility of the paint film enables it to withstand the stress of expansion and contraction cycles caused by outdoor temperature changes.

Wrinkling

PAINT DEFECTS: EXTERIOR

 a rough, crinkled paint surface occurring when paint forms “skin”.

Wrinkling

PAINT DEFECTS: EXTERIOR

Possible causes

• Paint applied too thickly (more likely when using alkyd or oil-based paints)

• Painting a hot surface or in a very hot weather.

• Exposure of uncured paint to rain, dew, fog/high humidity levels

• Applying top coat of paint to insufficiently cured previous coat.

• Painting over contaminated surface (e.g., dirt or wax)

Solution

• Scrape or sand substrate to remove wrinkled coating.

• Repaint, applying an even coat of top quality exterior paint.

STAINS

a solution of dye or suspension of pigment in a vehicle, applied to penetrate and color a wood surface without obscuring the grain.

Water Stain

TYPES OF STAINS

A penetrating stain made by dissolving a powder form dye dissolve in hot water as a vehicle.

Spirit Stain 

TYPES OF STAINS

A penetrating stain made by dissolving dye in an alcohol or spirit vehicle.

Pigmented Stain

TYPES OF STAINS

Also called opaque stain; an oil stain containing pigments capable of obscuring the grain and texture of a wood surface. Applied by wiping.

Oil Stain

TYPES OF STAINS

Made by dissolving dye or suspending pigment in a drying oil or oil varnish vehicle.

VARNISH

A liquid preparation of a resin dissolved in oil or in alcohol that when spread and allowed to dry forms a hard, lustrous and transparent coating.

Alkyd varnish

TYPES OF VARNISH

is the standard all-purpose interior variety with decent protective qualities.

Spar varnish or marine varnish 

TYPES OF VARNISH

It is a durable, weather-resistant varnish made from durable resins and linseed or tung oil

Polyurethane varnish

TYPES OF VARNISH

varnish of exceptionally hard, abrasion and chemical-resistant varnish made from plastic resin

Lacquer varnish

TYPES OF VARNISH

Refers to any of various clear or colored synthetic coatings of nitrocellulose or other cellulose derivative dissolved in a solvent that dries by evaporation to form a high gloss film; has moderate water resistance, but it’s sensitive to heat and certain solvents

Shellac varnish

TYPES OF VARNISH

spirit varnish made by dissolving purified lac flakes in denatured alcohol