In painting, as in life, some of the most important work is in the preparation. A good prep job is critical to the look and longevity of your paint job. As a professional painter, I know that techniques for surface prep are going to vary depending on many factors. For interior painting, glossy surfaces can be especially tricky; if you want your new coat of paint to adhere it is important to get this right. Glossier sheens such as semi-gloss and satin are especially common on doors, trims, windows and cabinetry. They are also preferred in kitchens, bathrooms and stairwells due to their ease in clean up and maintenance. If you are painting any of these areas, you need to be especially attentive to your preparation methods.
To do this right, you first need to know what kind of paint you are covering. If you live in an older house, built before 1978, it is critically important to know if you have any lead paint. Sanding lead paint is hazardous, and removal must be done professionally. So don’t take this lightly. As a member of the Indiana Chapter of the Painting and Decorating Contractors of America, Matthews Painting adheres to painting industry standards in dealing with lead paint. Coverage, as opposed to removal, is typically the best remedy, but each case must be determined individually. If you suspect you have lead-based paint, you need to consult a painting professional before proceeding.
Even if you don’t have to deal with lead paint, you need to know what kind of paint you will be covering to determine the preferred preparation techniques. There are important differences between oil and latex-based paint. Fortunately, it is easy to tell the difference. Just take a cotton swab soaked with ammonia or alcohol and rub an inconspicuous spot. If paint comes off, it is not oil-based.
Glossy surfaces can be the most challenging to prep and the most important to do right. If you are doing your interior trims or cabinetry, surfaces that often have a glossy sheen, you will need to prep it properly so that the new coat adheres. There are several techniques, but the ultimate goal is the same: you want the surface to be clean, dull and dry. In short, you need to remove the gloss.
There are several methods for de-glossing, each with their own benefits and disadvantages. Sanding is a great method for smaller areas such as trim and can be used for all types of surfaces, but can become a difficult job if you need to do a large area.
With chemical de-glossers you can clean and de-gloss in one step. These work better on latex. In the right circumstances, chemical de-glossers can be much easier than sanding. The issue may come down to whether you’d rather deal with dust from sanding or harsh chemicals requiring protective gear and ventilation.
Scouring with abrasive pads and a cleaning solution is another option to clean and de-gloss in a single step without the harsh solvents found in chemical de-glossers. It presents an alternative to sanding for oil-based paints, but can be messier as it often results in a drippy, wet sludge that will need to be removed with paper towels.
Even after you have de-glossed a surface, a coat of primer is usually recommended when painting over the glossier sheens. This can depend on the type of paints you are working with. For example, if you are covering an oil-based paint with latex, you definitely want to use an oil-based primer first.
It is worth looking at primers that are specially formulated for your particular conditions. There are many variables to consider, but some rules of thumb do apply. Generally speaking, it’s more important to use primer when dealing with glossier sheens. Primers are also crucial when you are covering old coats with a new type of paint (eg. oil to latex) or changing the sheen (eg. semi-gloss to flat).
Application methods – brush, roll or spray – may also influence the type of painting preparation work required. Whatever the particulars of your situation may be, Matthews Painting Company is always available to provide a complimentary consultation. Contact us anytime to assess what kind of prep work will be required to make your next interior paint job a success.