How to install attic ventilation for an energy efficient home

In hot temperatures, when cooling is the major concern, some attic insulation keeps heat from infiltrating the living spaces below it; but this is not a great concern, because hot air rises and cool air sinks. More important than insulation in hot weather is ventilation. On a hot day, enough air should be drawn through your attic that it doesn't feel like an oven, and you can sense a slight breeze as hot air exits through the roof.

• All the moisture produced inside a house needs to escape.
• In the heat of the summer, a well-ventilated attic allows hot, humid air to escape upwards; in the winter, good ventilation keeps the roof cold and prevents moisture from condensing and ruining the effectiveness of the insulation in the attic floor.
• Proper ventilation is particularly important if you are storing things in your attic.
• Neither heat nor moisture are good for storage areas, and both could damage your belongings while in storage in an ill-ventilated attic.

• If your attic needs new ventilation, gable vents are the easiest type to install.
• Your home should have a vent in every gable if you do not have other types of ventilation.
• Pre-made vents are available at nearly all home-supply centres. Cut an opening in the gable wall with a drill and saber saw. Attach the vent with screws or nails.
• Small plug-style soffit vents are easy to install with a drill and a hole-saw attachment. Hire a roofer or a carpenter to install larger soffit vents.

Ventilation and insulation go hand-in-hand, so make sure you have a complete plan when starting your project.

• Before you start an insulation job, check for vents in the soffit, gables, ridge and other places in the roof.
• See that insulation sits 2.5 centimetres (one inch) back from any vent openings.
• You may have to frame the vents with wood to hold the batting back.