PEER Presland
OCH’s Presland Net-Zero Prefabricated Exterior Energy Retrofit
OCH’s Presland Net-Zero Prefabricated Exterior Energy Retrofit (PEER)
Ottawa Community Housing’s Sustainability team has partnered with Natural Resources Canada on an innovative project that focuses on improving the energy efficiency of affordable housing by retrofitting homes to Net-Zero energy and Net-Zero Greenhouse gas emissions.
The Prefabricated Exterior Energy Retrofit (PEER) Pilot Project is a solution to breathe new life into four 70-year-old townhomes on Presland Road in Ottawa’s Overbrook neighbourhood.
This innovative retrofit involves the installation of prefabricated, insulated panels to the exterior of the home without the need to relocate tenants. To complete the work, the staff constructed a workshop dedicated to creating panels and brought the research to life with their innovation and hard work.
How does it work?
A highly insulated and airtight shell was built and placed over the home’s roof and existing walls, right down to the foundation. An electric heat pump heating and cooling system was installed, making the homes energy efficient and GreenHouse Gas (GHG) emission-free. Doors, windows and the roof were replaced. Finally, an array of solar panels were installed on the south-facing roof of the four townhomes. The solar panels will generate enough power annually to offset the consumption of the four homes – making them net zero.
PEER Presland
Frequently Asked Questions
- 1. How does this project benefit OCH and the tenants?
Ottawa Community Housing manages 15,000 homes throughout Ottawa. Two-thirds of the housing stock is more than 50 years old. The city’s Waiting List for affordable housing has more than 10,000 people.
We need to maintain our existing stock while building new affordable homes. This pilot is a deep energy retrofit, which is traditionally costly, slow and disruptive. At Presland, we were able to get funding for 50 percent of the cost of the project. The project also reduces the disruption for tenants by performing much of the work from outside the building while the building is occupied. This project has addressed many years of capital repairs while also improving the interior comfort of the unit and eliminating GHG emissions. The tenants benefit from a repaired, more comfortable home with central air conditioning.
- 2. At what stage is the project now?
Work began in the spring of 2020 and is now complete. The monitoring phase started in Sept 2021, and we are closely tracking the performance of the homes. We are working with our partners to report annually on the project’s performance.
The natural gas heating systems were replaced with electric heat pumps. The hot water tanks were replaced with a heat pump as well. Additionally, 35kW of solar panels were placed on the south-facing roof. The solar panels generate as much electricity as the building consumes each year, making the homes net-zero. New windows and doors were installed. Heat recovery ventilators were installed to keep as much heat inside the building as possible and reduce energy consumption. The new building envelope has 10 inches of insulation to keep the building warm and a new air and vapour barrier to make it airtight. This eliminates most of the building’s convective and conductive heat losses, maintaining the heat in the home and reducing energy requirements.
- 3. What’s next?
OCH has used the lessons learned from this project to create long term capital plan that aligns with the City of Ottawa’s Climate Change Master Plan, which aims to have all GHG emissions in Ottawa eliminated by 2050.