the painted surface
Painting Questions
These are some general painting questions that are often asked. We hope the answers will help you during your home painting projects. You may ask us a paint related question by contacting us.
The color of my aluminum or vinyl siding is out of style, can siding be painted?
Yes. Generally speaking, make sure the surface is clean and dry. Use an oil-based primer on aluminum siding if it is weathered. And do not use a paint color darker than the original vinyl siding color. Doing so may cause the vinyl siding to warp or buckle. More details and information is found in the article “How To Paint Aluminum or Vinyl Siding”.
The paint on the galvanized gutters and downspouts of my house is peeling. Help!
Traditionally there have always been problems with paint adhering to galvanized metal and especially gutters. Lack of adhesion may be caused by painting the metal without cleaning it first of a possible oily residue from the manufacturing of the gutter, or the use of oil-based paint which over time will peel due to water vapor coming through the metal and lifting the paint. It is now recommended to use acrylic paint on galvanized gutters and downspouts because it will “breathe” with the metal allowing the water vapor to pass. Short of stripping the gutters and starting fresh the best thing to do is scrape away (a carbide scraper will do a superior job but scrape safely and wear eye protection) the peeling paint, wipe with a degreaser if needed, prime with an acrylic bonding primer and paint with 100% acrylic paint. Thankfully, gutters are now mostly aluminum and copper which do not have the adhesion problems associated with galvanized metal.
Is a primer really needed before painting, what does a primer do?
There are several reasons to use primers. They are most useful on new surfaces like wood, drywall or metal. On wood and drywall a primer will seal and prepare the surface for caulking, patching and painting. On metal a primer provides an additional layer of protection against rust. All primers even out imperfections to some degree resulting in a smoother finish. Sometimes a primer is used to seal water, sap, and tannin stains to prevent them from bleeding through the finish coat. In the case of the typical interior wall built of drywall there are two surfaces, the paper layer of the gypsum board and the drywall compound or mud used to cover the seams and nail or screw heads. A good drywall primer will seal and even out these materials to provide a uniform base coat for paint. New drywall needs two coats of primer before hanging wallpaper. If the walls are not primed they will likely be damaged when the wallpaper is removed. The joint between molding and the drywall should be caulked after priming. The primer seals the wood and drywall improving the adhesion of the caulk. Exterior wood trim should always be primed first then caulked for the same reason. An acrylic bonding primer is used as an intermediate coat between two incompatible paints, such a when a water-based paint is used over an oil-based paint. During repaints some colors, mostly reds and yellows, will not cover or hide the previous color well. If the red paint you are using seems transparent and is not covering well a prime coat of medium gray or tan will help. A prime coat of white under yellow will improve the covering ability of the yellow. In these cases of color hiding you do not have to use a dedicated primer, you can use the same kind of paint as the finish coat.
This simple image illustrates some of the properties of a primer. The primer will fill the tiny voids in the surface of wood, metal and drywall much better than paint formulated to be a topcoat or finish coat. The primer forms a smooth even surface to provide a base for the finish coat. The solvents in the finish coat will meld with the primer coat to form a bond much stronger than a finish paint applied to a bare surface.
My metal lawn furniture is rusty and needs to be repainted, what is the best paint for metal lawn furniture?
Definitely an oil-based enamel after priming with a rust preventative primer. Oil-based paint will give the best protection from the sun and rain. It dries hard and can be easily cleaned with strong cleansers. Remove rust before priming with a steel brush. The primer will help prepare the metal and seal any old rust stains. A primer containing zinc chromate usually provides good rust prevention. Major paint dealers will match a color in their oil-based enamel paints if you want something different than the usual black or white.
The wallpaper stripper is not soaking through the wallpaper?
A good quality wallpaper will be coated with vinyl for durability and to make it washable. This is great until you want to remove the paper. The vinyl coating prevents moisture from penetrating the surface that would soften the paste and loosen the wallpaper. If you can keep the paper wet for a long enough period of time it will finally loosen but this may take several hours before the stripper penetrates the vinyl. One solution is to use what is known as a “Paper Tiger”. This wallper removal tool which can be found at most paint dealers and home improvement stores perforates the paper allowing the stripper to penetrate and dissolve the paste. The depth of scoring is adjustable for use on different thicknesses or multiple layers of wallpaper. If not used carefully it can cause some drywall damage leaving small holes in the surface which will probably require patching before painting the wall. Another solution is to sand the wallpaper with a coarse grit sandpaper to score the vinyl layer. You can use a hand sander as pictured in the photo or a vibrator sander. The hand sander pictured uses a half sheet of sandpaper.
One sheet should be enough to sand an average size room. The amount of sanding required will depend on the type of paper and the strength of the wallpaper stripper. The sandpaper should be 36 or 40 grit size. Do the sanding on dry walls before any of the surfaces are wet. The many scratches caused by the sanding will allow the stripper to penetrate very quickly. Having used both methods I believe the sandpaper is quicker and more efficient.
