Can I add insulation to the walls of an older home without removing the drywall?

Yes, you can add insulation to existing walls without removing drywall using blown-in or injection foam methods, though the effectiveness depends on your home's construction and current insulation levels.

The most common approach for Ottawa's older homes is blown-in cellulose or fiberglass insulation. A contractor drills small holes (about 2.5 inches) in the exterior wall from outside, then uses specialized equipment to blow insulation into each wall cavity. The holes are then patched and painted to match. This method works well for homes with standard 2x4 or 2x6 stud construction and can increase your wall's R-value from virtually nothing to R-12 to R-15.

Injection foam insulation is another option that's becoming more popular in Ottawa. This involves drilling smaller holes and injecting expanding foam that fills gaps and voids more completely than blown-in materials. It's particularly effective for older homes with irregular framing or existing settling. The foam creates both insulation and an air barrier, which is crucial for Ottawa's climate where air leakage can account for 25-40% of heating costs.

Ottawa-specific considerations make this upgrade particularly valuable. Many homes built before 1980 have little to no wall insulation, and with our -30°C winters, the energy savings can be substantial. You'll typically see a 15-25% reduction in heating costs. The work can be done year-round, unlike exterior renovations, making it perfect for fall and winter projects when HVAC contractors are less busy.

Professional installation is strongly recommended for this type of work. Improper installation can create moisture problems, especially in Ottawa's climate where vapor barriers and air sealing are critical. A qualified contractor will assess your wall construction, check for knob-and-tube wiring (common in pre-1950s homes), and ensure proper coverage without creating thermal bridging.

Before proceeding, have an energy audit done through Enbridge Gas's Home Efficiency Rebate program - you may qualify for rebates up to $5,000 for insulation upgrades. The contractor should also check for asbestos in homes built before 1980, as disturbing insulation may require special handling.

For a comprehensive assessment of your home's insulation needs and a free estimate on wall insulation upgrades, contact Justyn Rook Contracting. We'll evaluate your specific situation and recommend the best approach for your Ottawa home.