Do it Yourself

Do it yourself: a primer on paint primers

By Gene Austin
Friday, October 15, 2010; 3:02 PM

Q. What is the purpose of paint primers? Are they necessary when there are now self-priming paints, and are they as good as separate coats of primer and paint? Also, if I paint my bathroom white (it is now yellow) do I need a primer? -S. Lewis

A. The main purpose of most primers is to improve the adhesion of the finish paint by providing a non-glossy surface that binds the surface to be painted and the finish paint. However, there are many special-purpose primers; some of these seal in stains that would otherwise bleed through the finish paint, some control rust, some fill pores, some lock in odors, and so forth. Some primers are water-based and easy to use, some are oil-based and some have solvents such as shellac.

Self-priming paints have come a long way in the past decade, and a few of them, such as Valspar Ultra Premium Duramax and Behr Premium Plus Ultra, have achieved high ratings with some users. But not all users are pleased with self-priming paints; some say it takes two or three coats of self-priming paint to achieve the same results that can be achieved with one coat each of primer and regular paint. Self-priming paints are generally more expensive than regular paints, although in any contracted paint job, labor always makes up about 90 percent of the cost. My inclination is to stay with primer and regular paint for the time being.

If the yellow paint in your bathroom is in good condition, free of stains and is not glossy, you should not need a primer. You should use special bathroom paint, such as Zinsser's Perma-White, which resists mildew and could give one-coat coverage.

Q. I live in a small condominium with a loft attic and no basement. The tank-type water heater and gas furnace are directly over my bedroom. I am thinking of installing a tankless water heater. What are the pros and cons? Are tankless heaters efficient and reliable? -D. Cornwell

A. You have a gas supply, which is one of the requisites for a tankless water heater. The main advantage, of course, is the compact size, which eliminates the big storage tank of a conventional water heater. Other advantages, assuming the tankless heater is working properly, are an instant and steady supply of hot water and, in many cases, some savings in the cost of heating water. An income-tax rebate of up to $1,500 is available if an eligible heater is installed before the end of this year. Because of their compact size, tankless heaters can be installed in much smaller spaces than a tank heater. The main disadvantage is the installation cost, which is considerably more than a tank heater. Many tankless heaters need replacement after about 20 years. An experienced installer, a solid warranty and top product (see and search for Tankless Water Heaters), are you best protections.

QUICK TIP: Many do-it-yourselfers will be using extension ladders this fall for painting, gutter cleaning, roof repairs and other maintenance projects. Extension ladders are a great help but a hazard if not safely used. An important safety step is to place the base of the ladder on a firm surface and make sure it doesn't lean to either side. But setting the ladder at a safe angle against the building or other surface baffles many users. If the ladder angle is too steep, it can tilt backward when climbed; if not steep enough, the ladder can flex dangerously when climbed. A rule of thumb that can help get the ladder at the correct angle of 70 to 75 degrees is to estimate or measure the ladder's extended height, then put the base one-quarter of that distance from the building. For example, if the ladder is extended to 20 feet, set the base five feet out from the building; if the ladder is extended 24 feet, make it six feet.

Questions and comments should be e-mailed to Gene Austin at Send regular mail for Gene Austin to 1730 Blue Bell Pike, Blue Bell, Pa. 19422.

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