Primers and Paints

Primers and finish paints have different functions in the decorating process, and it's critical to understand the role each plays. Finish paints provide surfaces with a final, smooth layer of protection and a final color.
Primers are used to prepare those surfaces for finish paints and aren't suitable for finish coats.

Why Use Primers?

Without priming, new wood, plaster or drywall surfaces will soak up more finish paint in some areas than in others, producing a splotchy effect, and you end up using more paint to even out the finish, which is not economical because it's more expensive than primer.

In addition to sealing the surfaces, good primers will also cover different textures, like the difference between drywall and joint compound. And that's critical if you're using higher-gloss paints which tend to show those differences and imperfections more than flat paints.

A third benefit of using a primer is that it provides the finish paint a better bonding surface so it sticks to the base material much better.

Primers

Latex primers generally work best over drywall, plaster and concrete surfaces. They dry fairly quickly (usually about an hour) and are water soluble so they can be cleaned up with soap and water.

Alkyd primers generally work best on raw wood, they take a fairly long time to dry (usually overnight) and require mineral spirits or paint thinner for clean-up.

Stain-killing primer-sealers (often alcohol-based) are specially formulated to prime and seal problem areas like water stains on walls or knots in bare wood which can bleed through ordinary primers and show through the finish paint. They come in several formats: water-based, oil-based and shellac-based (which cleans up with alcohol). They usually cost a few dollars more per gallon, but are often worth the price for better coverage over trouble spots.

Finish Paints

Finish paints are categorized by the amount of surface shine they produce when dry. Terms like "gloss" and "flat" often dictate where such paints are used in the home but their use does overlap in some areas.

• High-Gloss Paints, often referred to as "enamels," are the shiniest and most reflective paints. They produce the hardest, most water-resistant and most washable surface coating, so they're most often used on wood trim and kitchen, bath and playroom walls. However, surface flaws show most when covered with high-gloss paint.
• Semi-Gloss Paints, also known as "eggshell," "velvet," or "satin" paints, produce a somewhat shiny surface that's more reflective than a flat paint but less reflective than a high-gloss surface. They resist moisture better than a flat paint, so they're more washable and serve well on walls in hallways, kitchens, baths, and children's bedrooms.
• Flat Paints leave a "dull" or "matte" finish, with no gloss, shine or reflectivity. They work best on irregular wall surfaces where you want to hide the imperfections as much as possible. Flat most typically used on ceilings, living rooms, and dining rooms over drywall surfaces.
  

Finish paints, like primers, also come in both latex and alkyd-based formulations.
In general, the latex products are best suited for drywall and the alkyd-based paints work best on wood trim.

Although latex formulations are improving all the time, alkyd-based high-gloss paints usually leave a smoother finish since they take longer to dry and have more time to level out brush marks which sometimes remain visible in latex paints.

Choosing Primers and Paints

When buying primers and paints, you can always find bargain brands costing one-half to one-third the price of the so-called "premium" products. And for many jobs, the bargain brands will work just fine.

But often, the premium products will give you more and better pigments and resins which produce better looking and longer lasting finishes.

With more pigments, they would also cover more thoroughly and require only one finish coat while a bargain brand might require 2 coats and wipe out the savings in price.

TIP: Have your paint supplier tint the white primer to match your finish paint. That way the color in the first coat doesn't get washed out by the white primer underneath, and it often eliminates the need for a second coat of finish paint.

Painting Without VOC's

Concerns about air pollution and hazardous household wastes have virtually eliminated the use of true "oil-based" paints which released high amounts of VOC's (volatile organic compounds).

Alkyd-based paints and latex paints are much safer, but alkyds and, to a lesser degree, latex paints do release some VOC's into the air, and even those reduced amounts bother a lot of people.

But there are now paints being formulated in both flat and eggshell finishes with no VOC's, and they produce virtually no odors when applied. So those are a definite option for people bothered by paint vapors.

Clean-Up

With both latex and alkyd-based paints, first squeeze excess paint from the brushes and roller covers back into the containers. There are inexpensive tools curved on one edge to scrape paint off roller covers.

With latex paints, let the brushes and roller covers soak in a pail of warm sudsy water, rinse them off and spin them with a spinner tool (which is designed for both brushes and roller covers) to spin off moisture. Repeat those steps as needed to finish the cleaning.

Use the combed side of a cleaner tool to loosen stubborn paint and then soak and spin the brush clean. Smooth out the bristles with the comb or a rag and allow it to dry thoroughly.

With alkyd-based paints, pour an inch or two of thinner or mineral spirits into a small metal can and swirl the brush in that to loosen the paint. Squeeze the excess off the brush and spin it dry inside a paper bag, a cardboard box or a 5-gallon plastic pail to keep from spraying thinner all over. Repeat as needed until it's clean.

The solvent may not dissolve paint that's already dried on the brush, but you can usually scrape that off with a metal-bristle brush or a metal comb. Once the brush is clean, smooth out the bristles and allow it to dry thoroughly.

TIP: When you're applying more than one coat of the same paint, you don't have to clean brushes or roller covers between coats. Just wrap them in plastic to keep them moist till you're ready to paint again.

Paint Disposal

Never pour excess paint down the drain--even latex paints.

The safest way to dispose of paints (alkyd-based and latex) is to leave them in their cans, set them outside with the lids off, let them dry completely and then bring the cans with the labels intact for proper identification to an approved disposal site in your community. If you don't know of such a site, call your city or county offices to find out the approved paint disposal process.

For small amounts of paints, you can also take the paint outside and pour it onto old newspapers, being careful not to let any get on the ground. Let the paint dry and then dispose of the newspaper in an approved manner.