Latex paints can be thinned with water and are easily applied. Compared to oil-based paints, the advantages of latex paints are:
- Less odor
- Water cleanup
- Rapid drying
- Easy touchup
- Easy application, even on damp surfaces
- Better gloss and color retention (less fading) on exterior surfaces
- No yellowing on interior surfaces
- Remains more flexible and less brittle, which makes them less likely to crack and peel.
The disadvantage, especially of some lower-quality or promotional products, are poorer adhesion to blistered, peeling or chalking surfaces, and, in some cases, less-effective hiding qualities.
Latex paint films on wood allow moisture to evaporate through the film, reducing blistering.
Oil-based paints consist of a pigment in a vehicle made up of resins and thinners. When thinners evaporate, the resins form a hard coating while the pigment forms the color.
Major advantages of oil-based paint are:
- Better penetration of the surface
- Better adhesion
- Better flow and leveling
- Dry to a smoother finish with fewer brush or roller marks.
The disadvantages of oil-based paints are the odor, cleanup with solvents or thinners and longer drying time. Also, oil-based paints cannot be applied to moist surfaces.
INTERIOR PAINTS AND ENAMELS
Interior paints are available in flat (no shine), satin, semigloss and gloss (high shine).
Enamels provide a high-gloss washable finish for hard-wear areas or for rooms such as the bath and kitchen that require a high resistance to moisture, dirt and grease. Today, companies not only sell high-gloss, but eggshell or even flat enamels. Interior paints are sold in various formulations-oil based, alkyd based or synthetic based, latex, etc.
Interior paints are sold in various formulations-oil based, alkyd based or synthetic based, latex, etc.
Flat paints usually have an alkyd- base that thins with turpentine or mineral spirits, or a latex base that thins with water. Latex paints are usually vinyl or acrylic based or a combination of the two.
Alkyd flat paints may hide better with one coat than will comparable latex flats, but brushes and other tools must be washed with turpentine or a similar solvent. Latex flats spread easily, especially on porous surfaces, and seldom require a primer. Tools clean with water.
Flat wall paints are usually applied to ceilings and walls, except in kitchens and baths. Semigloss or gloss paints withstand the frequent washings required in these two rooms.
For windows, doors, wood trim and other woodwork, satin, semigloss or gloss enamels are recommended. These surfaces get more wear than walls, more fingerprints and soil. Because glossier enamels wash more readily, they are more desirable.
Semigloss latex paints serve well as finishes for wood-trim areas. They have the advantage of water cleanup.
Because enamels and gloss paints dry rapidly, more care must be exercised in application because they tend to brushmark, especially on hot, dry days. Preparation of interior surfaces is vital to good end results. Surfaces must be free from grease, dirt, mildew, chalking, etc., washed well, thoroughly rinsed with clear water and allowed to dry before repainting. Cracks and holes must be repaired and patched areas spot primed.
If surfaces are badly soiled, a trisodium-phosphate (TSP) cleaner may be necessary. However, phosphates are a recognized pollutant and TSP is more prone to deposit crystals that impair adhesion than do some other products.
When repainting glossy surfaces, sufficient cleaning materials must be used to dull surfaces, or they should be lightly sanded. An alternative to sanding is the use of a liquid cleaning/dulling solvent. High-gloss surfaces typically do not provide good adhesion for new coats of paint.
Painting over wallpaper is not recommended; the old covering should be removed. Once painted, wallpaper is extremely difficult to remove.
|Wash all grease and dirt off walls and woodwork.||Don't expect good results on dirty surfaces.|
|Patch cracks in walls and ceilings before painting.||Don't paint over a damp surface with oil-base paints.|
|Seal all new surfaces with a primer.||Don't apply the second coat of paint until the first coat has dried properly.|
|Scrape off all loose paint and sand the surface to a smooth finish.||Don't sand woodwork across the grain.|
|Stir paint thoroughly before any applications.||Don't change cans of paint in the middle of a wall area.|
|Allow new plaster to dry before painting.||Don't add thinner to the product unless directions call for it.|
|Properly ventilate area to be painted.|
Latex- and oil-based house paints are formulated to withstand wear and exposure to severe weather conditions. Many manufacturers offer specific formulations for regional climates.
Surface preparation is critically important for good adhesion. Proper preparation includes scraping as much old paint as possible from the surface, sanding to feather edges of scraped areas, washing the surface with a good detergent solution, repairing chips, cracks, splinters, etc., cleaning and sealing nail heads.
Major problems encountered with house paints are generally due to:
- Failure to completely clean surface of dirt, grease, old paint, etc.
- Excessive moisture
- Painting damp surfaces
- Painting under adverse weather conditions
- Failure to use proper primer coat
- Failure to follow manufacturer's directions
Any of these conditions can cause blistering, peeling, early fading or other similar problems.
Trim paints are bright colors, chosen to contrast with the house color. They dry quickly to a hard finish; they are primarily for use on window frames, shutters, railings, etc. and are not recommended for large surfaces.
Masonry surfaces include stucco, concrete, cement, asbestos shingles, etc. Most masonry paints are latex based; some are acrylic based. Oil-based paint is not recommended for masonry because of the residual alkalinity in the masonry.
Latex-based masonry paints require a special pretreatment or bonding primer to "tie down" old chalk and dust before application. They dry to a flat finish.
Rough surfaces should first receive a coat of block filler. Acrylic elastomeric coatings bridge cracks and pinholes to provide the best waterproofing.
Powdered cement paints, which have a shorter exterior life than latex coatings, must be mixed with water. They can be applied only over a porous masonry surface such as brick, stucco or concrete, or over surfaces that have been previously coated with this same kind of paint. For proper adhesion, the old surface must be wetted down thoroughly and the paint applied to the damp surface.
Masonry paint can be waterproof as well as decorative. For best color retention, coat with a good acrylic-latex paint 30 days after application of a waterproof masonry paint.
PAINT FOR GUTTERS
Both latex- and oil-based paints adhere well to galvanized steel and aluminum gutters. Oil based works better on tin gutters.
Galvanized gutters require priming both inside and out and should be cleaned with coarse cloth dampened with paint thinner before they are painted, or should be left unpainted for three to six months so the weather can etch the surface for better paint adhesion.
Oil-based paints should never be applied directly to unpainted galvanized metal. They will eventually peel off. A galvanized metal primer must be applied first. Acrylic-latex paint can be applied directly to unpainted galvanized as long as it has been cleaned thoroughly.
Many shingle paints (really stains) are low in pigment content, leave light color on the surface, and are used primarily to provide surface protection for wood shingles.
In some instances, shingle paints may be applied without a primer. Where the surface is badly weathered, recommendations may call for a companion primer, undercoater or two finish coats.
Most shingle paints have oil or alkyd-resin base, which thins with turpentine or similar solvent.
Floor paints, also called deck enamels, are for "walk-on "surfaces. Ordinary high-gloss enamel is not suitable. Floor enamels are formulated to withstand weather and wear on wood and concrete. Available in both oil based and latex, the latter dries to a flat finish while most oil-based products dry with a medium- or high-gloss finish.
Oil-based paints are not recommended for many concrete surfaces, especially those in contact with round moisture, such as basements and patios, because they will not adhere to damp surfaces. The alkali in concrete may combine with the oil to form a soap, resulting in poor adhesion, peeling and paint lifting from the surface.
Concrete floors which have been penetrated by oils, gasoline, etc., are virtually impossible to paint because it is extremely difficult to clean these surfaces well enough to make paint adhere.
A final advantage of latex floor paints: The homeowner can lay resilient floor tile without removing the old paint. This is not possible with other floor paints.
Conventional floor paints work poorly on garage floors. Car tires get hot as the car is driven, and when the hot tires come in contact with the floor paint, the paints sticks to the tires and is lifted off.
Many gloss floor paints are slippery when wet and a nonskid additive should be considered.
SPECIAL PURPOSE PAINTS
ACOUSTICAL CEILING PAINT
Special acoustical ceiling paint forms a porous film which will not harm noise-reducing properties of acoustical tile.
Its consistency is much like regular wall paint so it can be applied with a brush, roller or sprayer.
High-quality aluminum paint is aluminum blended with a resin base. It works equally well on almost any surface and may be brushed or sprayed. Colors become more intense with age.
Aluminum paint can be used on all interior and exterior metal or wood surfaces, or applied to metal flashing, gutters, downspouts, tools, tool sheds, patio furniture, pipes, mailboxes, fences, etc.
Do not apply aluminum paint during freezing temperatures; paint should dry at least overnight before re-coating.
Texture paint is a good answer to problem walls and ceilings; it is thick bodied enough to seal most minor imperfections (large holes and cracks must be filled) and leave a decorator finish. It is available as a liquid base with tinting colors or as a powder in several colors.
Texture paints come in several consistencies, ranging from smooth formulas to larger-texture particles in sandy textures, all the way to coarse stucco finishes, which create the deepest texture.
Depending upon the desired visual effect and the specific coarseness of the paint, brushes and rollers, putty knives, trowels and other applicators can be used to create a variety of patterns or designs such as swirls and deep-texture finishes.
After these finishes have been applied and allowed to dry, the surfaces can be painted any color. Texture paint also may be tinted prior to application.
Lacquers, the fastest drying of all finishes, are available in clear or colors. Because of fast-drying characteristics, they are usually difficult to apply by brush. However, some manufacturers do offer specially formulated "brushing"-type lacquers that apply more easily with a brush. Lacquer thinners are required to clean tools.
The secret to successful application is to work fast, not going over same spot twice. For beginners, use a 50/50 mixture of lacquer and lacquer thinner, preferably made by the same manufacturer.
Lacquers are hazardous to handle. Fumes are noxious and in a closed room can be dangerous to the user; furthermore, fire and explosion hazards are much greater than with ordinary paints and varnishes.
Lacquers cannot be used over old paint or varnish because the solvents will lift old finishes. Lacquers should be applied to new wood only or over previously lacquered surfaces.
Epoxy finishes are primarily for bare or previously finished wood floors, and eliminate "dusting" when applied to concrete floors. They do not darken or change the color of wood to any degree. They penetrate rapidly and can be applied with a brush or mop.
An epoxy finish adheres to most surfaces and is especially good for doors, cabinets, trim and furniture: any interior wood surface where a clear-gloss, easy-to-clean finish is desired. Resists detergent, oil and alkali, but may lose gloss under exposure to sun and weather.
Finishes are formulated in one- or two-part systems. Two-part epoxies come in kits containing equal-sized cans and contents are mixed; epoxies can be tinted. They are more chemical and abrasion resistant than one-component epoxies.
Conditioners are added to oil-based or latex paints to keep edges wet longer, prevent lapping, make paint cover better and lessen drag on the paint applicator. Conditioners also lessen paint clogging in spraying systems.
Insecticides are added to paint for outdoor use only, to eliminate pests nesting on painted surfaces. Insecticide paints contain chloropyrifos, a poison that insects absorb through their feet. The insecticide is poured into the paint which is applied as usual. Insects susceptible to the poison include spiders, ants, silverfish, ticks, roaches and earwigs.
Some manufacturers warn that additives may not do what they claim. They may also have adverse effects, such as increasing mildew growth. They may also void paint warranties.
Primer/sealers work to eliminate stains (including stains from water and fire damage), cover wood imperfections, hide wallpaper designs and serve as a foundation coat on metals over which a finish coat is applied. They also seal the surface evenly so a topcoat will have uniform gloss.
There are three basic types: alkyd based, latex based and shellac based. The alkyd and latex types work well as stain killers and general-purpose primers on both interiors and exteriors.
The shellac-based type blocks out the widest variety of stains, including knots and sap streaks in new wood, and adheres to slick surfaces such as glass and tile. This type is recommended for general-purpose priming on all interior surfaces, but should only be used for spot priming on exterior surfaces.
Acrylic or vinyl-acrylic latexes are the most frequently sold latex-based primers, but vinyl-based types are available. The term "latex-based" includes vinyl, acrylic and vinyl-acrylic copolymer types.
Wood sealer is used on soft woods to help tame wild grain patterns and even-out stain absorbency. The sealer penetrates the wood, slowing stain absorbency for a more even color appearance and grain pattern.
Stains accent grain without hiding it and protect the wood surface. There are two types of stain: semitransparent and semisolid. Semitransparent stains can be applied over bare wood or previously semitransparent stained (but not sealed) wood. Solid color stains can be applied over bare wood, previously stained and even painted surfaces in sound condition.
Exterior stains are used primarily on wood siding and shingles, decks, outdoor structures and furniture. They are available in latex and oil-based formulas. Latex stains do not typically fade as rapidly as oil stains. Latex stains are often recommended for redo over previously oil-based stained or painted surfaces due to their excellent adhesion properties.
Latex is recommended for woods such as cedar, redwood and cypress that have natural resistance to rotting. However, putting a light-colored stain on these woods can result in brown discoloration of the stain. Oil-based stains also take more abuse than latex types.
When staining exterior wood decks, only semitransparent oil-based stains should be used. If the deck is made of pressure-treated wood, it should be stained two to five months after installation.
Water-repellent preservative stains contain a fungicide and a water repellent, protecting against decay, mildew, warping, splitting and cracking, as well as wood deterioration. They can be oil- or latex-based stains in semitransparent and transparent finishes.
Interior stains, used for furniture and woodwork, come in either pigmented or dye categories. Both can have oil or synthetic bases.
Pigmented stains color the wood with the same type of pigments used in paint. They range in color from almost clear to semitransparent. They are easy to apply, usually brushed on or wiped on with a rag, and then wiped off to control the depth of the stain. They leave no brush or lap marks if applied properly.
Stains are generally used to enhance the grain of the wood and emphasize grain contrasts. They may or may not protect the wood; check manufacturers' labels. An oil or polyurethane finish is generally mixed with the stain, so the do-it-yourselfer can complete the staining and finishing job in one step.
Dye stains are more difficult to use and are more frequently used by professionals. Most come in powders, to be mixed in a solvent. Most are highly flammable. Premixed dyes are most often used by the d-i-y-er.
Dye stains offer deeper penetration of wood surfaces and less grain hiding. However, they also fade more quickly than pigmented stains and require more effort to prepare the wood.
Water-based dyes tend to raise the grain on many woods because the water penetrates the wood and raises the tiny fibers. Wood should be wetted first, then sanded down, before applying water-based dyes.
Nongrain-raising (NGR) dyes are dissolved in a NGR solvent. They dry faster than water-based counterparts, so application must be faster to avoid lap marks.
Colored oil finishes, such as Danish oil, tung oil or Swedish oil, provide coloring and protection in one step. However, oil finishes do not stand up to alcohol or water the way polyurethanes do, so they are not recommended for high-traffic, abuse-prone applications.
But oils make nice, low-luster finishes for furniture and other fine pieces. Waxing can provide water resistance with these finishes.
Varnish is a blend of oils and resins that coats the surface of wood and gives a transparent, protective coating, allowing the beauty of the wood to show through. Depending on its formulation, it can leave a gloss, semigloss or satin finish.
All varnishes must be applied to a clean, dust-free surface in a dirt-free area with a clean brush. Dust can damage the wet surface.
Varnishes fall into four groups, divided by their base: alkyd, polyurethane, latex, or phenolic. Varnishes are typically mixed with a tung oil or linseed oil.
Phenolic varnishes of modified phenolic oils are the most expensive of the varnishes but deliver the best performance in terms of durability, especially in exterior uses. They absorb ultraviolet light and neutralize oxidation. The downside of phenoics is that they tend to yellow faster than other varnishes.
Alkyd varnishes offer flexibility and hardness in both interior and exterior uses, but they oxidize more quickly in exterior use. However, they do not yellow as much as phenolics.
Polyurethanes are not generally recommended for outdoor use. They yellow and crack when exposed to ultraviolet light unless ultraviolet light absorbers are added to make the polyurethanes more durable for outdoor use. Check manufacturer specifications.
Polyurethanes are highly recommended for interior use because of their superior protection. For interior use, phenolic or polyurethane stains are better for water resistance and hard use, but customers may object to the plastic appearance they produce. Alkyds offer a natural-looking gloss for furniture and indoor architectural trim and doors.
There are varnishes that offer the cleanup convenience of water-based latex coatings. These varnishes combine polymers with urethane or acrylic polymers. These water-based products offer the advantages of oil-based coatings and the cleanup convenience of water. The acrylic coatings take from one-half hour to 1 1/2 hours to dry and do not yellow the wood. Some acrylic-based varnishes are durable enough for use on floors.
Except for two-package or moisture-cured urethanes, exterior clear finishes do not last as long as pigmented stains or paints.
Shellac provides a fast, hard-drying, durable finish for furniture, woodwork, hardwood floors and other wood-finishing applications. It also functions as a sealer and stain killer on drywall, cured plaster and new wood. Shellac is widely compatible with other coatings, and it can be applied over old shellac, varnish or lacquer finishes that are adhering well.
Most shellac is sold in a "3-lb. cut," the consistency recommended for most uses. The 3-lb. cut can be thinned to a 1-lb. cut for applications such as wood sealer before staining by thinning one quart of shellac with three pints of alcohol.
For applications where water spotting may be a problem, protect shellacked surfaces with paste wax or varnish.
Shellac may be applied with a brush, foam brush or from an aerosol can. When brushing, flow on the shellac from a full brush with minimum brushing, and do not re-brush areas, since shellac's alcohol-based solvent dries quickly. Shellac offers convenient cleanup in ammonia and warm water.
All wood preservatives must contain an EPA-registered fungicide to classify as wood preservatives. Pressure-treated wood, with lifetime warranties, does not require a brush-on preservative coating. Brush-on preservatives are used for untreated wood and should be reapplied periodically.
They are generally classified as one of three types. A clear alkyd or oil-based type without fungicide is sometimes called log oil or log-cabin finish. The second type has the same base with fungicide additives of penta, cuprinol or a preservative. The third type consists of a non-paintable preservative containing wax or creosote oil, primarily for farm use.
Wood preservatives for the d-i-y-er generally should be paintable.
Wood preservatives by themselves provide no protection against moisture or water. Water repellency must be formulated into the product. The preservative chemical used varies according to need and type of exposure.
Waterborne, water-repellent preservatives for wood offer lower environmental hazards and convenient water cleanup. They provide an alternative to conventional solvent-based water-repellent preservatives while retaining effectiveness, rapid drying qualities and excellent paintability. Another preservative, 3-iodo-2-propynyl butyl carbamate, is offered in some of these waterborne preservatives.
A water repellent helps minimize water damage on pressure-treated and untreated wood. Some water repellents also contain a mildewcide to help control mold and mildew growth. It's best to use a water repellent that is formulated for immediate application to pressure-treated wood to avoid premature cracking, splitting, splintering and warping. Periodic re-applications help prevent water damage as wood ages.
WOOD-TONER WATER REPELLENTS
Wood toners are water repellents that add color to highlight wood grain. Although toners are not to be considered a stain, adding color to a water repellent gives wood the benefit of ultraviolet light protection. Most toners on the market are designed for use on pressure-treated wood. Not all repellents contain ingredients that cause water to bead.
|About two thirds of the homes built before 1940 and one-half of the homes built from 1940 to 1960 contain heavily leaded paint. Some homes built after 1960 also contain heavily leaded paint. The sale of lead-based paint for residential use was banned in 1978. Lead can be on the walls, the woodwork and on the outside of houses.|
|Lead paint in good condition is not usually a problem except in places where painted surfaces rub against one another and create dust. For example, when you open a window, the painted surfaces rub against one another. In older buildings where the paint is not in good condition, lead paint can chip off or wear off. Lead dust and chips can also be created during preparation of surfaces for painting and during renovating or remodeling. The dust and chips are especially hazardous to small children.|
|Lead can be harmful even at Iow levels. Even children who appear healthy may have high levels of lead in their blood. You can't tell if a child has lead poisoning unless you have him or her tested. In many cases, the harm lead causes cannot be reversed.|
|Being exposed to lead can affect a child's mental growth. Lead interferes with nervous system development, which can cause learning disabilities and impaired hearing. Children with lead poisoning may complain of headaches or stomach aches or become very grouchy, but they often show no symptoms of lead poisoning.|
|Adults can get lead poisoning through occupational exposure as well as through home renovation and remodeling activities. In adults, lead's health effects include high blood pressure. In extreme cases, lead poisoning can cause comas, kidney or brain damage, or death.|
|If you are remodeling, test for lead paint first. Some local health departments offer a lead testing service. If this service is not available, you should hire a qualified inspector.|
|If high levels of lead are detected, you should not attempt to remove the lead paint yourself. Instead, you should hire a person who is specially trained to correct lead paint problems, who knows how to do the work safely and has the proper equipment to clean up thoroughly. Improper removal of heavily leaded paint can endanger the health and lives of the entire family.|
|Contact the National Lead Information Center at 1-800-LEAD-FYI for information. The purpose of this federally funded service is to provide information to the public on lead.|
Check your state and local codes before starting any project. Follow all safety precautions. Information in this document has been furnished by the North American Retail Hardware Association (NRHA) and associated contributors. Every effort has been made to ensure accuracy and safety. Neither NRHA, any contributor nor the retailer can be held responsible for damages or injuries resulting from the use of the information in this document.