FEATURES OF STAINS AND PAINTS - PART II
This is part 2 of a 2 part series of articles on paints and stains.
Exactly What You Are Looking For - Interior Paints Coatings for Each and Every Job
Did you ever wonder about the difference between interior and exterior paints? I once used exterior paint on an indoor ceiling, reasoning that it would last longer. It could last longer, but as I found out when I needed to touch up the ceiling only 2 years later, exterior paints will discolor on an inside surface. Exterior paints contain special additives made to withstand the outdoors. Interior paints have additives that help the paint dry to a durable, uniform finish.
A lot of the advances in painting technology have been with latex. Actually, latex has overtaken oil-based paint in several areas: durability and elasticity, as well as ease of application, clean-up, and disposal. Latexes have fewer VOCs than oil-based paints. Some, including the Pristine brand created by Benjamin Moore, are created with no VOCs in any way. Today's latexes are created with higher quality pigments and binders that provide them more body, so they go on thicker.
Latexes enjoy quite a bit of reputation for interior applications, specifically for walls and ceilings. Alkyds stay the professionals' choice for trim work because oil based paints are better to paint on detailed areas like molding and hardwood trim. However, that traditional approach is slowly changing as better latexes, including Pratt & Lambert's Accolade Interior Acrylic Semi Gloss, come on the market.
High Demand Exterior Paint Coatings
Moisture is an important consideration for exterior paint selection. Every day a family of four will generate several gallons of vaporized water inside a house.
Coupled with naturally occurring humidity, this may mean a lot of moisture moving through the wall surfaces and siding. Moisture is highest in the baths and kitchen. If these rooms aren't sufficiently ventilated, water will migrate through the wall space. Vapor barriers help to contain wetness, but vapor always seeks to leave. The structure of a residence, the type of vapor barrier they have, ventilation, and dampness all make selecting the right paint critical.
In wetter climates you need a paint that will let moisture pass through the wood, so water doesn't get trapped under the paint and cause blistering and peeling. Latexes are porous and let dampness pass through, unlike alkyd paints, which form a waterproof seal. Alkyds also don't flex with areas that expand and shrink, as wood does, especially in colder climates. Latex paints have more elasticity, allowing better adhesion.
I prefer using latex on most exterior areas, including wood siding, stucco, and cement. Latexes avoid fading better than most oil-based paints, and they'll cover either oil-based or latex primer (most oils have to go over an alkyd primer).
Latexes perform a great job of covering concrete. Despite its hardness, concrete is very porous, and oil-based paints don't always adhere well. For ideal durability, I would recommend latex enamel.
In general, if I know of a latex product that provides superior performance, I'll choose it over an oil-based product that must be cleaned with a thinner.
Latex only requires water. Thinners add yet another expenditure, are hard to get rid of, and usually end up spattered on my skin or clothes, regardless of how careful I am.
Amazing Way to Use Stains for Interior Work
You are able to spend a life time studying stains and sealers, but there's nothing mysterious about them. The bottom line in determining which stain to make use of is to familiarize yourself with the product lines available. Scan the label, along with any product information you can get, and talk to the staff at a professional paint shop.
Outside stains come in oil based, varnish, polyurethane, and water-borne solvents. Stains have less colorant than paint plus more solvents, providing them with higher wood penetration. Waterproofing is a priority with exterior stains. Most come with built-in sealants to add sturdiness and help maintain the wood. The color in stains can be pigments, dyes, or both. A semi-transparent stain has more dye for grain penetration. A solid stain has more pigment for surface covering. Pigment is a finely ground coloring that doesn't penetrate the grain as deeply as a dye. That's why a pigmented stain is usually accompanied by a sealer such as urethane or varnish.
Some high quality interior stains have dyes to penetrate and pigments to draw out the richness of the grain. Others contain only pigments, that are better to apply, combine, and touch up. Pigmented stains are lighter in color and draw out more of the wood grain. If you're looking for darker results, a dyed stain will provide what you want in one overcoat (be sure to use a conditioner on porous wood, such as pine and birch wood, to avoid splotching). Dyed stains are almost impossible to touch up. Every coating eventually will require touching up, so make certain to consider ease of maintenance in your choice of stains. You'll receive the best results by using better stains such as Minwax, Pratt & Lambert's Tonetic, Pittsburgh's Rez, or Wood-Kote.
If you wish to stay away from the watery nature of stains, get a gel stain, which had the majority of the water solvent removed. Gels are easy to use. They spread on, dry fast, and cover evenly. Because they're colored with pigment, gel stains don't penetrate that well. They're a good choice for porous woods that are hard to coat evenly with out a toner. Gel stains do a excellent job of showing off the grain on embossed metal or composite surfaces. I don't recommend working with them for hardwoods, which need a good dye stain to emphasize the depth and beauty of the grain.
No-Fuss Painting Using Sanding Sealers
Sanding sealers are interior primers that both penetrate and seal wood. You should use them under clear coats or on top of stains as sealers. Sanding sealers are different from a sealer like polyurethane, which is not made to prime. They're more like varnish, but diluted with solvents to allow better penetration for priming. The hardness of varnishes and lacquers inhibits them from soaking in to the wood pores. Sanding sealer can provide a better bond for clear coats.
Shellacs tend to be added to sanding sealers to fortify the resin and provide an instant drying agent. In addition they add an amber tone, so if you're utilizing a sanding sealer with shellac, make sure it won't influence the stain. Shellacs have a tendency to yellow aver time and contain toluene, that has a high VOC content. Shellacs are gradually giving ways to new sanding sealer formulas with lower VOCs and better performance.
Alkyd resin sanding sealers also have high VOCs, although significantly less than their shellac based cousins. Pittsburgh Paints makes a slow dry alkyd resin sanding sealer without shellac named Rez 77-1. This specific primer/sealer is good for both interiors and exteriors. Pratt & Lambert's Latex Sanding Sealer has suprisingly low VOCs, but is purely for interior wood and must not be used under a water borne polyurethane.
Oil-based sanding sealers can also be utilized to seal outside wood, especially decking, which is continually subjected to sun and water. For color consistency in areas like decks, it's best to completely coat, or back prime, the wood before it is in place, using the same sealer or stain. Olympic Water Guard, Messmer's UV Plus, Behr's, and most top quality deck stains are great water repellent sealers that also can be utilized for priming outdoor wood.
No-Fuss Wood and Stain Sealers for Interior Wood
Sealers, including varnishes, lacquers, urethanes, and shellacs, are put into the stain itself, applied as a top coat on top of a stain, or used as a clear coat on unstained wood trim. They could be used for just about any type of wood trim, including windows, doorways, and the casing around them. Although you can purchase stain/sealer combinations, they have a tendency to yellow, are difficult to maintain, and don't last as long as separately applied stain and sealers.
Varnishes contain natural oils such as Tung oil, a very hard, durable sealant that may be brushed on and dries slowly. Varnishes are easy to clean and keep maintaining with soap and water accompanied by a wiped on varnish, which usually keeps a wood surface looking ideal for years. Make sure there's no wax in your cleaner, because wax clogs wood pores. I prefer to work with Hope's Tung Oil varnish for a wipe-on maintenance layer. Lacquer is a fast dry sealer that more often than not needs to be sprayed, since it becomes tacky almost immediately.
Polyurethanes do almost anything shellac can do, but they're better to maintain. While shellacs act like paint, polyurethanes act more like a clear coat that permeates the wood instead of sitting on top of it. Polyurethanes brush on and dry quickly, with little stench and VOCs. They have more or less replaced shellacs as a clear sealer. Another reason urethanes have grown to be such popular sealers is that they don't really require sanding sealers.
The smells associated numerous paints and stains can become more than just offensive, they can be toxic. Solvent based varnishes, lacquers, and shellacs provide a super hard finish but contain high VOC levels. Water borne sealers, like the stains, match the performance of many solvent based sealers, with fewer VOCs. The VOC content of water based sealers such as Sherwin Williams Kern Aqua Lacquer average about 250 grams per liter, or 2 pounds per gallon, half the usual VOCs of oil-based lacquers. The ethers in water borne sealers aren't combustible, another advantage, but they still have enough VOCs to warrant a respirator.
Although they resist yellowing, water borne sealers such as acrylic latex polyurethanes do have a tendency to raise the grain. They'll also harden or "flash off" quickly at conditions higher than 60°F. The very best working temperature for most water borne acrylic latex polyurethanes is between 50°F and 60°F, which lets them flash a little more slowly. In cases like this, flashing-off simply means that the solvent evaporates and leaves the resins to complete the drying out process. A contractor I knew once used water based latex polyurethane sealer that flashed off so fast he could only put it on between 5 A.M. and 9 A.M. Anything later than that was too warm.
Minwax makes very good water borne polyurethane, as do Pittsburgh, Pratt & Lambert, Benjamin Moore, among others.
Amazing Stains and Sealers for Exteriors
Because of their better penetration and sealing power, most exterior stains sold today are oil-based. However, oil-based solid stains peel as they grow older, making them more difficult to maintain. A solid stain is like paint: It coats more than it penetrates. A latex solid stain peels less which is better to maintain as it ages. However, I prefer oil-based products for semi-transparent stains. Added oil solvents let them penetrate deeper. Some of the better stains on the market include Pittsburgh Solid Color Latex Stain, Messmer's U.V Plus, Moorwood Solid Color Exterior Stain, Sherwin Williams Woodscape stains, Pittsburgh Semi-transparent Exterior Stain, Rez Deck Stain by Pittsburgh, and the Sikkens Cetol system.
Deck stains usually have more solids than a typical outside stain, which will make them more durable. I recommend buying a high-end stain that is semi-transparent or what's called a trans-oxide. Until lately, the significant problem with exterior stains was their low UV resistance, but newer trans-oxides have finely ground metal mixed in for greater protection. A high end deck stain won't need a different sealer coating, although you can include one (such as Olympic Water Guard) if you think extra protection is required to battle moisture and sun exposure. Better deck stains retail for approximately $35 a gallon and cover 300 to 400 sq. ft.
Stay away from deck stains that contain silicone. Despite their attractive price, they are not a good deal. Advertisements for silicon stains and deck sealers often show beaded up water on the deck, and many people are fooled into thinking that this is actually the indication of an effective coating. However, silicon deteriorates quickly, usually in a matter of months, producing a discolored, waxy coat that is clearly a pain to eliminate. The deteriorated silicone also ceases repelling water.
"High build" coatings such as Sikkens and Messmers work remarkably well on exterior siding, however they are too soft to be utilized on your deck. Eliminating these coatings needs gallons of wood cleaner and a significant amount of work.
Water borne exterior stains, such as Sherwin Williams Woodscapes, combine the advantages of oil-based and latex coatings. They run and drip less than oil based stain, and dry faster, allowing for two coatings the same day. Water borne stains possess the resilience and flexibility of the latex stain, giving them stamina. They're a good choice for some applications. But bear in mind that cleaning up water based stains will take work. There are a couple of oil components in the solvent which have to be cleaned. First use soap and water, then alcohol. Ask your seller for specific cleaning guidelines for water borne stains, and read the label.
When In Doubt, Ask Questions
If you still have questions about which paint or stain to make use of, please ask people in the know. An experienced, educated salesperson can answer any questions you might have. Choose a paint store with staff having at least a decade of experience in the business. Inquire further what has worked best for your unique application and ask to see a spec sheet on the product in question.
The answers you get will depend on whom you ask. A paint store will try to sell you one their own products, in the end, that is why they're running a business. Painting contractors might not be impartial, either. They have to sell their experience. I get a lot of cell phone calls from people looking for help with their painting problems. Most painters, including myself, don't mind giving an hour of time, but if you want in depth answers, consider finding a contractor for a professional analysis. Rates vary, but I usually charge about $60 for a written and oral examination, with respect to the driving time included. A paid examination will tell you whether you should paint, stain, or re-side, as well as which finish might be best for your project. Each painting job has unique conditions that warrant specific answers.
Sound Quality Painting
824 90th Dr SE suite B
Lake Stevens WA 98258
(425) 512-7400
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