Adding attic insulation delivers the greatest return on investment for most Canadian homes. As energy prices rise, it means deeper applications of attic insulation make more economic sense. Even homes built to code just two years ago may not meet the minimum levels required for new homes today.
Start by aiming for a minimum of R50 as an end goal. The R-value is a measure of thermal resistance. If there is loose, fluffy insulation in your attic it has a value of about R3 per inch. If it is blanket-like batts it is about R4 per inch.
You will need to measure and calculate what you have so that you will know what you need to add. If you do not have at least 16 inches of insulation in your attic you’re letting money waft out of your home.