Plan ahead

More costly but effective cooling measures are available as your home undergoes normal upgrades and repairs.

• A 10-year-old air conditioner, for example, is only half as efficient as a new one. A quick check of your air conditioner's efficiency can help you decide whether to call in a service professional. Use a household thermometer to measure the temperature of the discharge air from the register and the temperature of the return air at the return-air grill. (Keep the thermometer in place for five minutes to get a steady temperature.) The difference should be from 14 to 20 degrees, experts say. An air conditioner that's not cooling to those levels could be low on refrigerant or have leaks. A unit cooling more than 20 degrees could have a severe blockage.
• Using light shingles on a new roof can cut the amount of heat the house absorbs. Repainting in a light color, especially south- and west-facing exterior areas, helps as well.
• Upgraded insulation in the attic and double-paned windows all around, complete with tinting to reflect sunlight, are good ideas, too.