As the host of season 2 of The World’s Greenest Homes, John Bell traveled the world touring the world’s greenest homes, speaking to the owners, builders and designers about the homes and what made them decide to build more sustainable housing. The homeowners had built these homes to lead greener lifestyles and lower their carbon footprint. Clearly his work influenced his next move: after finishing season two of The World’s Greenest Homes, John and his family sold their large three storey home in a beautiful but somewhat isolated Toronto neighbourhood, to a home a little more than a stone’s throw to mid-town Yonge Street with all of its advantages. In the process they cut their home’s footprint in half, and probably their transportation footprint in half too.
The house John and his wife purchased was an old 1970s house on a cul-de-sac with single-paned windows, little insulation and plenty of air leaks. In fact when the energy auditor did the home’s audit pre-renovation, it came it at a leaky 7.7 air changes per hour and an Energuide rating of 33 out of a possible 100. In terms of what those numbers mean, according to the Office of Energy Efficiency, a home’s Energuide rating of 0-5o is an older, unrenovated (uninsulated) home. At the opposite end of the scale, an Energuide rating of 91-100 is an airtight home with proper ventilation that requires no extra heat source. The Air Change measurement measures the number of times the volume of air in the house is being replaced through leaks in the home’s envelope approximately.
The Bells added another 800 square feet to the home’s footprint while renovating the house. Even so, when the energy auditor tested the renovated home, the Energuide rating rose to 80, and the air changes per hour dropped to 1.59 ACH.
Given his experience on The World’s Greenest Homes, John noted that every homeowner he interviewed had the goal of decreasing their carbon footprint by building a well-insulated, low carbon footprint home. So like the green homeowners before him, John concentrated his efforts on his building envelope and improving his home’s energy efficiency.
John hired John Godden from Clearsphere to help him achieve his energy efficiency and green building goals. John Godden has been an active member of the green building realm way before it became the place to be in construction. His firm was one of the partners involved in building the EcoLogic Community in Newmarket, ON, the first LEED Platinum community built in Canada.
Building envelope: The ceilings have an R-value of 41, the new construction 2×6 walls of the addition have an R-value of 26, the older 2×4 walls, an R-value of 22. All are insulated with Roxul batt and rigid board insulation.* Roxul is a locally produced mineral-wool-based insulation with a high recycled content that is also a good fire retardant and noise damper. The basement floor and below grade basement walls were insulated with Roxul Drainboard with an R-value of 10, and below grade walls have an R-value of 32 as they have additional batt insulation inside the house. Roxul batt and rigid board insulating products were used for most of the insulation work. There were spots in the house, however, where the best insulation was spray foam, so he used Icynene.
Windows are from Ridley, aluminum-clad wood interior windows, double-glazed with a low-EQ coating that helps block strong sun rays and heat in the summer so the air conditioning unit doesn’t have to work as hard.
HVAC: The system is a 98% efficient boiler-fan coil system combined with duct work provided by Airmax Technologies. The boiler heats water for both domestic hot water, radiant heating. It works in conjunction with a forced air system. John also had a Power Pipe installed which is a drainwater heat recovery (DWHR) system. DWHR can save you up to $125 per year depending on how much hot water you use (the more hot water used in the morning for showers, the more money it will save you). Radiant heating was installed in the basement to keep the floor warm, in front of the windows on the main floor at the front and back of the house, and in the two second floor bathrooms. A heat recovery ventilator was installed to capture heat from warm stale air, and to ventilate the now very tight house with warmed fresh air coming from outside.
Solar Sheat 1500G Air Panel. This is an interesting bit of new technology that John admits was installed more for the concept than for a specific return on investment. The way it works is, the panel sits on a south facing roof top where it can absorb the sun’s rays. Cool air is sucked up from inside the house, next it is warmed by the panel on the roof and blown back into the house via a vent. It has an optional solar PV panel used to operate the fan so that no additional electricity is needed. The single solar air panel provides enough heated air to heat 750 square feet, the approximate size of the second floor of John’s home. John said that with the tight envelope of the home, the heated air will help keep the second floor warmer even after the sun goes down, meaning the boiler. The system costs $16oo plus $2000 to install.
Water Efficiency: Another area John noted where green home builders were concerned was with water conservation. John became interested in gray water recycling, and in fact is now vice president of Greyter Water Systems a distributor of Brac Gray Water Systems. He installed a Brac gray water tank in his home and says that it provides more than enough water from showers to flush the toilets in his home. He also installed dual-flush toilets.
Green technologies: John figures that during the renovation, he spent an additional $28,000 on green technologies, including $10,000 for solar panels to be part of Ontario’s microFIT program. The energy upgrades John made will save him $4000 per year in energy costs vs. his previous bills, so his payback point comes in at around 7 years and that’s assuming energy prices stay at 2011 levels — which they won’t. The longward trend for energy pricing is definitely upwards.
In the end, John is aiming for Silver certification level of LEED Canada for Homes and will likely achieve it.
Update January 3, 2018: Roxul has rebranded as RockWool. Visit its website for more information.