When my wife Luisa and I bought our home on Boothroyd Avenue in 2011 we knew our 2.5 story, 2-bedroom semi-detached home would not meet the needs of our growing family. We also knew that our 100+ year home would require significant retrofits to meet the needs of our environmentally conscious family.
Our existing home had wood cladding at the rear, insulbrick cladding at the side, and brick the front, all with very little insulation.
We made the decision to add a full third story and implement a deep retrofit to improve the energy efficiency of our home. In working with Sustainable T.O., the following energy efficiency upgrades were implemented:
House feature
|
Before retrofit |
After retrofit |
| Exterior Walls |
Wood and Insulbrick Cladding (no insulation)
|
Wood and Galvalume Cladding (7” Rockwool Insulation R28) |
| Windows |
Single Pane, Single Hung with wood frame
|
Double Pane, Fiberglass |
| Roof |
Flat Roof (no insulation)
|
Flat Roof (Sprayfoam Insulation R37) |
| Heating System |
Low Efficiency Natural Gas Furnace
|
High Efficiency Natural Gas Furnace and Air Source Heat Pumps for 3rd floor
|
As a result of the energy efficiency upgrades, the natural gas consumption in our home has decreased by half from approximately 2400 m3/year to approximately 1300 m3/year. It is also a much more comfortable and quieter indoor environment.
There were economic benefits in making the decision to add a third story and completely gut our existing house with implementing the energy efficiency upgrades. Our existing cladding, windows, and heating system were at the end of their useful life which made the decision to add additional insulation very feasible.
Our retrofit experience was not entirely smooth sailing and had a few bumps along the way. At the beginning of our of renovation we were only planning to apply 1.5” rockwool insulation on the outside of our existing home, but due to some water ingress from a rainfall event we were forced to remove all the existing interior drywall. This then enabled us to install 5.5” rockwool insulation between the interior wood studs. In removing the drywall we also discovered significant mold buildup that had accumulated over time and also found the wood stubs in the kitchen had been eaten by termites impacting the structural integrity of the house. With a 100-year old home, there were benefits of gutting the house that extended beyond energy efficiency benefits.
In hindsight, one of the decisions we would have changed in our reno was the air sealing approach. We went with the standard Tyvek housewrap rather than Blueskin which was more expensive. At the time we did not know the importance of air sealing. Also, for our heating system, we simply replaced our old furnace with a high efficiency one and installed an air source heat pump to provide supplemental heating and cooling to our third floor where we sleep. In hindsight we should have developed a more robust roadmap for transitioning fuel source and considered an air source heat pump to heat and cool our entire home. Although 5 years ago at the time of this decision, it was not presented as a viable option.
Looking ahead, my family is now developing a 5 year plan to transition our fuel source away from natural gas and further improve the energy efficiency of our unfinished basement which was not part of the reno, but is now the weakest energy efficiency link in our home.
