I have a two story house with a ridge vent on top and gable vents on both sides of my house, the house was built in 1988. I am having a problem with the upstairs staying hot during the day so I started to investigate. I noticed that there are no soffit vents anywhere around the house. My question is with existing gable vents will it be ok to install soffit vents around the house to get better ventilation and take advantage of the ridge vent or will it affect it in a negative way?
Joe L. ~ Tulsa, Oklahoma
Adding more ventilation will not hurt anything with your current venting situation. The addition of additional attic venting will most likely result in a negligible drop in your upstairs room temperature. There are lots of theories on attic venting and I have experimented with most of them and here is some of what I have learned. Even if you install a thermostatically controlled gable vent fan, the interior cooling benefits will be minimal. It is the radiant heat not the convective heat that heats your ceilings. This sounds like bad news, but there are some ways to combat this problem. More insulation in the attic will slow down the temperature rise in the upstairs, if you have skylights upstairs, cover them on the outside with an opaque cover, or install an attic vent fan. I have had the best luck with very high CFM (cubic feet per/minute) attic fans installed in an upstairs ceiling. When this type of fan is turned on, it purges all of the hot air in your upstairs and replaces it with cool air from the rest of your house of from outside. These fans are great in the evenings because they can fill your home with nice cool evening air in a very short period of time while the fan is running and windows are open. Good luck!