To one degree or another, residential homes are insulated – the exterior walls; the roof and attic; even the basement. But as many homeowners are bound to discover, not all insulation performs up to scratch. The result – poor overall energy efficiency, and energy bills that are higher than need be. The thing is, a good part of a home’s structure (known as the “building envelope”) is exposed to the exterior elements. This provides an opportunity for air to flow in and out of the home, setting the stage for poor energy efficiency throughout.
The idea behind insulation is to prevent airflow. It means preventing heated indoor air from escaping in the winter, and preventing hot outside air from coming into the home in summer. In this respect, a reputable insulation contractor can determine whether exterior or interior retrofitting is best for the insulating project at hand. As well, the contractor can be valuable in determining the type of insulation product to use, and the installation method that best meets the need. For the homeowner, performance and affordability will be key.
There are a number of determining factors when choosing between exterior and interior retrofitting. For the typical homeowner, it is good to understand the basics – it will make for a better working relationship with the contractor and will make for better decision making throughout the lifespan of the project.
- assessing the exterior/interior finishes of the home and the ease of a retrofit
- considering the physical construction of the home and the potential for changes
- evaluating other renovation work that might be expedited all at the same time
- calculating the extent of energy savings that could be achieved with each option
Interior insulation retrofits clearly offer advantages (and consequent cost savings). Firstly, all the work can be performed year round. Secondly, there is much less demolition required. And thirdly, there are far fewer construction and bylaw ramifications. Additionally, where other renovation work may affect any interior finishes, this is the perfect opportunity to seal and insulate. Indeed, where a basement is getting renovated, a professional insulation retrofit can deliver superb results in personal comfort and annual utility savings.
When it comes to a major retrofit project, like installing a new “air barrier system” for the entire home, then the exterior option is preferable. Here, an insulation retrofit can deliver the maximum in performance – a seamless, airtight, envelope of insulation right around the home. Obviously, exterior work won’t affect the interior finishes, and won’t have any impact on the occupants. And as long as the budget permits, the new “air barrier system” will contribute greatly to both structural durability and insulating performance.
Speaking of budget, any insulation retrofit should take into consideration the initial project investment, and the longer-term “payback” period. Here again, a reliable contractor will be invaluable in working out project options that best suit the homeowner’s priorities and budget. And in many cases, the annual savings on heat and air conditioning will offset the original project investment.