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Stains:
Oil vs Latex:
See Binders at TrueArt.info Life span of different kinds of finishes: at the USFS Forest Products Laboratory (FPL)
Tips/Notes:
There is no such thing as water base. Water is a solvent for water-borne coatings. Water-borne finishes can contain oils, alkyd resins, epoxy resins, polyurethane resins, etc. These are the various kinds of binders. They all have different properties. To apply water base to them as a means of explaining their values is not only misleading it is stupid.
Semi Transparent vs. Opaque (solid-color): They also come in Oil and Latex. At Finishes for Exterior Wood Surfaces: Options For The Painting Contractor on Historic HomeWorks.com web site they say: Semi-transparent stains are probably the most popular and widely used of all the natural finishes. These products are available in a wide variety of colors but, like the other natural finishes, they are penetrating and, thus, do not fail by blistering, flaking, or peeling in the way that film-forming coatings may fail. Solid body, solid color, or solid hide stains are much more similar in nature to paint systems than they are to semi-transparent stains. These products, whether water-based acrylics or oiled-based solvent-borne systems, form a coating on the wood surface, hiding most of the wood and usually dramatically altering the color of the natural grain and character of the wood. When applied over extractive rich woods such as redwood and cedar, acrylic solid color stains should be applied over a top quality oil- or alkyd-based primer specifically formulated for extractive rich woods. As with the other finishes previously discussed, where the manufacturers' formulations allow, a minimum of two coats should be applied for the best performance. Solid body stains may need re-application every five to seven years. Coatings such as these are not recommended for decks and walking surfaces. Varnishes and other clear film-forming finishes are generally not recommended for use on exterior wood due to their rapid failure from UV light.
Latex over Oil: Once a surface is properly prepared and primed it is not an issue to apply oil over latex or latex over oil. Modern primers will accept either over either. We would not recommend using a latex primer to be coated with an oil finish in most exterior cases due to the difference in flexibility, but an oil/alkyd primer under latex finish paint is a good method.
Links:
Application: Spray-only applications are appropriate on smooth surfaces where rollers or brushes will leave undesirable finishes. These would include smooth lap siding, garage doors, exterior metal doors and some gutters. In these cases, it's recommended to spray on a good quality enamel exterior finish with a fine orifice tipped sprayer to achieve professional factory-finished results. The Wagner Power Roller speeds up painting, but it is a bear to clean. If you only have a moderate sized area to paint it may not be worth it. Natural bristle brushes should be used for oil-based paints and stains, and not for water-based or latex products because they get limp.
Stains: Latex semi-transparent stains do not penetrate the wood surface, but they are easy to apply and less likely to form lap marks. These stains are film-forming and are not as durable as oil-based stains.
Unlike paint, a solid-color stain may leave lap marks.
Products: Article at SFGate Deck Cleaners/StrippersThere are a number of sources of discoloration of wood decks. These include:
Until about ten years ago there were few, if any, products of this type on the market. Most coatings manufacturers recommended that decks and other exposed wood surfaces be cleaned before refinishing. The usual recommended cleaners were household products such as detergents for dirt removal and liquid bleach for mildew removal. Household cleaners and bleaches can be effective to some extent but they have their limitations. Also, since they are not usually designed for deck cleaning applications they can present some handling problems to do-it-yourselfers and contractors. For example, liquid household bleach should not be mixed or used directly with ammonia or any other detergents or cleaners containing ammonia since the resulting chemical reaction can form a potentially dangerous gas. About ten years ago products began appearing in the market that were specifically designed to clean and restore weathered wood surfaces such as decks and siding. Today there are a variety of such products available. Deck cleaners and restorers generally fall into one of three categories--chlorine bleaches, oxygen bleaches, or oxalic acid-based formulas. Each of these is discussed below. Chlorine-Based Bleaches Common types of chlorine bleach used in deck cleaning products are sodium hypochlorite, calcium hypochlorite and dichloroisocyanurate. The first two are typically used in laundry detergents while the last is a swimming pool additive. The most commonly recommended dilution is 3:1 (25% bleach). These chemicals are effective against mildew but do little to remove dirt or other surface deposits (which is why bleach alone does not get clothes clean). When used on wood decks, chlorine-based bleached products can do more harm than good. They can result in the wood's having a whitish unnatural tone due to the bleaching of natural components or a fuzzing of the wood's surface due to the loosening of small fibers during the cleaning process. Moreover, if not rinsed properly, the chlorine salt residues can result in premature graying of wood from the action of sunlight. As noted previously, household bleach and other products containing chlorine-based bleaches should not be mixed with products containing ammonia. Oxygen-Type Bleaches Products in this category are usually based on disodium peroxydicarbonate, commonly known as sodium percarbonate, an ingredient present in some color safe fabric bleaches. Sodium percarbonate is a powder. When added to water it forms hydrogen peroxide--a common oxygen bleach--and sodium carbonate (soda ash). Hydrogen peroxide is commonly used as a disinfectant and a stripper of hair coloring. On wood it is effective in removing mildew stains and weathered gray residue from UV (sunlight) degradation. The sodium carbonate acts as a built-in detergent, removing dirt and other deposits. Thus, sodium percarbonate-based cleaners are effective in removing dirt, mildew and weathered gray residues. Once treated, the wood returns to its natural original appearance. Oxalic-Based Products Certain wood species such as cedar and redwood contain natural resins known as tannins. These are water soluble materials which are reddish brown in color. Water can extract the resins from within the wood and deposit them on the surface, leaving brown or black discolorations. Tannins can also react with iron present in fasteners or nails resulting in blue-black stains. Neither chlorine bleaches nor oxygen bleaches are effective against tannin stains or iron stains. Oxalic acid, on the other hand, solubilizes tannins and iron stains and renders them colorless. Thus, it is the material of choice for use on redwood or cedar. However it can discolor the wood (see below). However, oxalic acid is not as effective against mildew. For this reason some homeowners and contractors will treat redwood and cedar with a sodium percarbonate or chlorine-based cleaner and follow it up with an oxalic acid-based product if tannin staining is apparent. Concentrating oxalic acid is toxic and should be handled and used with car. Paint Strippers.......... Sometimes, in order to restore a wood deck and prepare it for refinishing, the previous finish, or what's left of it, will need to be removed. Most deck cleaners and restorers are not effective in removing paints and stains. This can be accomplished by mechanical removal or chemical means. Mechanical removal will be discussed in the next section. Chemical paint strippers are usually based on organic solvents, caustic salts such as sodium hydroxide or sodium metasilicate. Most of these strippers are pretty potent and require some care in use and handling. Contact with skin or eyes must be avoided. Proper protective clothing and equipment must be worn as outlined on the product labels. Depending on the formulas, strippers will remove varnishes, oil-based stains or latex stains and paints. Most are supplied as ready-to-use liquids. Residual amounts of the stripper should be thoroughly rinsed from the wood before any product is re-applied since residual traces of caustic salts can interfere with subsequently applied coatings. Mechanical Cleaning.......... Mechanical methods for cleaning and restoring the surface of wood decks include planing, sanding, and power washing. Planing removes the outer surface of the wood face exposing fresh, new wood. Decking boards have to be removed from the structure and passed through a planer to accomplish this. Planing is very effective but its usage is limited by the need to physically disassemble part of the deck to carry it out. Since planing removes the outer veneer of wood it also results in a change in physical dimensions of each board. Sanding is effective as a mechanical means for removing unwanted coats of previously applied finishes. It can, however, damage the surface of the wood. On redwood and cedar sanding often results in an excessive amount of tannin resin bleeding. Power washing is the mechanical method for cleaning and restoring decks most favored by contractors. Power washers direct a pressure jet of water at the wood surface. This pressurized water is effective in removing dirt, mildew, algae and gray weathered residue from most wood surfaces. It can also be effective in removing previously applied coatings. Some contractors have found that the best cleaning procedure is to treat with a chemical cleaner and follow up with a wash/rinse from a power washer. Power washers are available to homeowners through purchase or rent from many paint or home center stores. First time users need to be cautioned since excessive pressure can damage wood deck surfaces. If not used properly power washers can also cause damage to windows, doors and siding. Major damage (in the form of texturing) can be done to smooth cedar by someone who was not experienced with a power washer! For this reason many do-it-yourselfers prefer to stick to chemically based means of cleaning and restoring their decks. Refinishing.......... As noted previously, proper surface preparation of weathered decks is an essential first step to the successful refinishing of these substrates. Failure to remove dirt, mildew and weathered residues is an open invitation for early failure of subsequently applied coatings. Care should be taken to thoroughly rinse all cleaner/restorer products from the wood. In addition, many coatings require all dry surfaces prior to application, so contractors and homeowners should allow adequate time for the wood to dry before applying a finish. Source: Cleaners And Restorers For Wood Decks And Siding at Historic HomeWorks.com
Products:
Bio-wash Stripex by Napier SuperDeck Wood Stripper
At Sikkens Simply Beautiful Wood Care Products they say:
At MasterHandyman.com
they say: Deck FinishesFinishes should be designed for decks; Otherwise, they may deteriorate rapidly under foot traffic.Stained wood surfaces may need to be retreated every 2-3 years or earlier depending on weather exposure. Aliphatic elastomeric urethane waterproofing systems are UV resistant, VOC compliant and provide a flexible, seamless, watertight, non-porous film over most treated surfaces.
Application:
At Finishing Wood Decks from Historic HomeWorks.com they say:
Peeling:
Comments on "Your Life Forum" at bostom.com says:
At weatherall.com they say:
Deck Finishing Links:
Links:
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