FEATURES OF STAINS AND PAINTS - PART 2
This is part 2 of a 2 part series of articles on paints and stains.
High Demand Interior Paints Coatings for Each and Every Job
Do you ever wonder about the difference between interior and exterior paints? I once used exterior paint on an inside ceiling, reasoning that it would last longer. It could endure longer, but as I then found out when I was required to touch up the ceiling only 2 yrs later, exterior paints will discolor on an inside surface. Exterior paints contain special additives designed to withstand the outdoors. Interior paints have additives that help the paint dry to a durable, uniform finish.
Most of the advances in painting technology have been with latex. Actually, latex has overtaken oil-based paint in several areas: toughness and elasticity, as well as ease of application, clean-up, and disposal. Latexes have fewer VOCs than oil-based paints. Some, such as the Pristine brand created by Benjamin Moore, are made with no VOCs at all. Today's latexes are made with higher quality pigments and binders that provide them more body, so they go on thicker.
Latexes enjoy quite a lttle bit of acceptance for interior applications, especially for walls and ceilings. Alkyds stay the professionals' choice for trimming work because oil based paints are simpler to paint on detailed surfaces like molding and trim. However, that traditional school of thought is slowly changing as better latexes, including Pratt & Lambert's Accolade Interior Acrylic Semi Gloss, come on the market.
Problem Solved - Finally, Exterior Paint Coatings for Every Job
Moisture can be an important consideration for exterior paint selection. Each day a family group of four will create several gallons of vaporized water in the house.
Coupled with naturally occurring humidity, this can mean a a large amount of moisture moving through the wall space and siding. Water is highest in the baths and kitchen. If these rooms aren't sufficiently ventilated, water will migrate through the surfaces. Vapor barriers help contain wetness, but vapor always seeks to leave. The structure of a residence, the sort of vapor barrier they have, ventilation, and humidity all make choosing 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 water go through, unlike alkyd paints, which form a waterproof seal. Alkyds also don't flex with surfaces 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 resist fading much better than most oil-based paints, and they will cover either oil-based or latex primer (most oils have to go over an alkyd primer).
Latexes do a great job of covering concrete. Despite its hardness, cement is very porous, and oil-based paints don't always adhere well. For very best durability, I recommend latex enamel.
In general, if I know of a latex product that will provide superior performance, I will choose it over an oil-based product that must be cleaned with a thinner.
Latex only needs water. Thinners add yet another expenditure, are hard to dispose of, and usually finish up spattered on my skin or clothes, no matter how careful I am.
Improve Your Staining for Interior Work
You are able to spend a life learning about stains and sealers, but there's nothing mysterious about them. The bottom line in figuring out which stain to make use of is to become acquainted with the products available. Read the label, along with any product information you can get, and talk to the personnel 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, giving them better wood penetration. Waterproofing is important with exterior stains. Most come with built-in sealants to add toughness and help maintain the wood. The colouring 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 coating. Pigment is a finely ground coloring that doesn't penetrate the grain as deeply as a dye. That is why a pigmented stain is often used along with a sealer such as urethane or varnish.
Some high quality interior stains have dyes to penetrate and pigments to bring out the richness of the grain. Others contain only pigments, which are better to apply, mix, and touch up. Pigmented stains are lighter in color and draw out more of the wood grain. If you are looking for darker results, a dyed stain provides what you would like in one coat (make 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 be sure to consider the ease of maintenance in your choice of stains. You'll get 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, try a gel stain, which had most of the liquid solvent removed. Gels are easy to use. They spread on, dry fast, and cover evenly. Since they're colored with pigment, gel stains don't penetrate that well. They're a great choice for porous woods that are tough to cover evenly with out a toner. Gel stains do a great 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 can use them under clear coats or over stains as sealers. Sanding sealers are different from a sealer like polyurethane, which is not designed to prime. They're more like varnish, but diluted with solvents to permit better penetration for priming. The hardness of varnishes and lacquers stops them from soaking into the wood pores. Sanding sealer provides a better adherence for clear coats.
Shellacs are often put into sanding sealers to strengthen the resin and provide an instant drying agent. In addition they add an amber tone, so if you are by using 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 very high VOC content. Shellacs are gradually providing ways to new sanding sealer formulas with lower VOCs and better performance.
Alkyd resin sanding sealers likewise have high VOCs, although significantly less than their shellac based cousins. Pittsburgh Paints makes a slow drying out alkyd resin sanding sealer without shellac called Rez 77-1. This specific primer/sealer is wonderful 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 based polyurethane.
Oil-based sanding sealers also can be used to seal outdoor wood, especially decking, which is constantly exposed to sun and water. For color reliability in areas like decks, you need to completely coat, or back prime, the wood before it goes up, using the same sealer or stain. Olympic Water Guard, Messmer's UV Plus, Behr's, and most top quality deck stains are excellent water repellent sealers that can also be utilized for priming outdoor wood.
Improved Wood and Stain Sealers for Interior Wood
Sealers, including varnishes, lacquers, urethanes, and shellacs, are added to the stain itself, applied as a top coat over a stain, or used as a clear coat on unstained wood trim. They can be used for any type of trim, including windows, doors, and the casing around them. Although you can buy stain/sealer combinations, they tend to yellow, are difficult to maintain, and don't last as long as separately applied stain and sealers.
Varnishes contain oils such as Tung oil, an extremely hard, durable sealant that may be brushed on and dries slowly. Varnishes are easy to completely clean and maintain with soap and water accompanied by a wiped on varnish, which usually keeps a wood surface looking ideal for years. Make certain there is 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 coat. Lacquer is a fast drying sealer that almost always needs to be sprayed, since it becomes tacky almost immediately.
Polyurethanes do almost everything shellac does, but they're much easier to maintain. While shellacs act like paint, polyurethanes act more like a clear coat that permeates the wood instead of resting on top of it. Polyurethanes brush on and dry quickly, with little smell and VOCs. They have more or less replaced shellacs as a clear sealer. Another reason urethanes have become such popular sealers is that they don't require sanding sealers.
The smells associated with many paints and stains can become more than just offensive, they can be toxic. Solvent based varnishes, lacquers, and shellacs give 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 most common VOCs of oil-based lacquers. The ethers in water based sealers aren't combustible, another advantage, but they still have sufficient 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 will also set up or "flash off" quickly at temperatures greater than 60°F. The best working temperature for nearly all water based 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 process. A contractor I know once used water based latex polyurethane sealer that flashed off so fast he could only use it between 5 A.M. and 9 A.M. Anything later than that was too warm.
Minwax makes very good water based polyurethane, as do Pittsburgh, Pratt & Lambert, Benjamin Moore, and others.
Stains and Sealers for the Exterior
Due to their better penetration and sealing ability, most exterior stains sold today are oil-based. However, oil-based solid stains peel as they get older, making them more challenging to maintain. A solid stain is similar to paint: It coats more than it penetrates. A latex solid stain peels less which is easier to maintain as it ages. However, I favor oil-based products for semi-transparent stains. Added oil solvents let them penetrate deeper. A number 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 will often have more solids than a typical exterior stain, which will make them more durable. I would recommend buying a high-end stain that is semi-transparent or what's called a trans-oxide. Until just lately, the significant problem with outside stains was their low UV resistance, but newer trans-oxides have finely ground metal mixed in for better protection. A higher end deck stain won't need a separate sealer coating, although you can add one (such as Olympic Water Guard) if you believe extra protection is required to fight dampness and sun exposure. Better deck stains retail for approximately $35 a gallon and cover 300 to 400 sq. ft.
Stay away from deck stains which contain silicone. Despite their attractive price, they aren't a good deal. Advertisements for silicone stains and deck sealers often show beaded up water over a deck, and many people are fooled into thinking that this is the indication of a successful coating. However, silicone deteriorates quickly, usually in just a matter of months, producing a discolored, waxy coat that is a pain to eliminate. The deteriorated silicone also quits repelling water.
"High build" coatings such as Sikkens and Messmers work remarkably well on outside siding, nevertheless they are too soft to be used on your deck. Eliminating these coatings calls for gallons of wood cleaner and way too much work.
Water borne outside stains, such as Sherwin Williams Woodscapes, combine the features 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 based stains possess the resilience and overall flexibility of any latex stain, giving them stamina. They're a great choice for some applications. But bear in mind that cleaning up water borne stains takes 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 supplier for specific cleaning guidelines for water borne stains, and scan the label.
Ask Your Painting Professional When In Doubt
If you still have questions about which paint or stain to make use of, please ask people in the know. An experienced, knowledgeable salesperson can clear up any questions you might have. Choose a paint store with staff having at least 10 years of experience in the business. Inquire further what has worked best for your particular application and ask to see a spec sheet on the merchandise in question.
The answers you get will rely upon whom you ask. A paint store will try to market you one their own products, after all, that's why they're in business. Painting contractors might not be impartial, either. They need to sell their competence. I get tons of phone calls from people seeking aid with their painting problems. Most painters, including myself, don't object to giving one hour of time, but if you want comprehensive answers, consider finding a contractor for a professional examination. Rates vary, but I charge about $60 for a written and oral analysis, depending on the traveling time included. A paid analysis will let you know whether you should paint, stain, or re-side, as well as which covering might be best for your project. Each painting job has unique conditions that require specific answers.
Sound Quality Painting
824 90th Dr SE suite B
Lake Stevens WA 98258
(425) 512-7400
