During GreenBuild 2011, there was a tour of three green houses offered, so of course I had to go on it! We saw three homes all in different stages of construction. The last house we saw was none other than The Rosedale House which I covered in July, 2010 during renovation. Terrell Wong and her husband Lindsay are the homeowners, but Terrell also happens to be an award-winning architect and the current president of Passive Buildings Canada so she knows what she’s doing when it comes to green renovations. Terrell took a classic Rosedale home with no insulation and turned it into, well, a classic Rosedale home with lots of insulation. She didn’t enlarge the footprint, she kept as much of the original woodwork and trim as possible (virtually all of it), sanded floors instead of replacing, and even kept the kitchen cabinets, but sent them out for restaining. The house was stripped back to the brick bones and insulated with Heatlok Sprayfoam insulation with an additional layer of cellulose in the attic. Because Terrell wanted to avoid as much thermal bridging as possible, nothing was allowed to break the thermal envelope that wasn’t absolutely necessary. The electrician might have cursed her initially, but complied with her request, so electrical outlets are located in the floor and inside walls only.
The end result is that the Wongs spent about $50,000 in thermal renovations (including insulation, boiler, energy recovery ventilator, hot water tank and German-made passivehouse certified windows. While that may seem like a lot, consider that the energy (heat and electricity) bills pre-renovation came in at about $1000/month or $12,000 annually. Now the energy bills for heat and plug load (no gas is used for any heating or appliances) come in at around $200/month or between $2000-$2500 per year.
As Terrell pointed out on the tour, it is easier to see the kind of payback they did on their house because they were basically starting from zero — as in zero insulation, inefficient oil furnace, minimal electrical upgrades. Houses that are already insulated, even if they were insulated 20 years ago, wouldn’t see the same type of financial improvement because they are starting from a higher, more insulated level. As always, however, the first place to start when you’re considering doing any building envelope and HVAC improvements is with an Energy Audit. Using an approved energy auditor can help you save money on any upgrades you make, and also direct you to making the right investments first. ie., insulation, weather-stripping and caulking before a new adding a new furnace.