Ottawa Community Housing (OCH), Ottawa’s largest social housing provider, is an organization dedicated to providing safe and affordable housing to enable its tenants to participate in the city’s socio-economic opportunities. Knowing that better management of heating costs can
bring important savings, OCH teamed up with Demtroys Technologies to assess the impact of a new heating management system on one of their building. If the results are successful, OCH could consider installing other systems in its building portfolio and expect savings on a larger scale.


Built in 1972, but had major retrofit during from July 2010 to
December 2014, including new windows, doors, and a new roof.
The heating system for the residential units is electrical
baseboard, while the common area heating and ventilation
system uses natural gas as the heating energy source

High-Rise Buildings





By working with Demtroys, OCH could eliminate wasted energy in overheated units while maintaining a comfortable interior temperature throughout the building. The Demtroys system uses 5 main ways to reduce the amount of energy required for heating. Zoning and modulation are the first steps. The OCH building has been separated into 24 different zones. These are mainly based on their level and orientation. Then, by measuring the outside temperature, the Demtroys system’s modulation algorithm adjusts the amount of energy needed to maintain the required temperature in each unit at any time of the day. For more information on the other ways the Demtroys system reduces energy consumption, please visit our website, or contact one of our advisors.

Ottawa Community Housing was pleased to see results right after the installation. This graph shows that the electricity consumption has greatly decreased following the installation of the Demtroys System, even if, according to an outdoor temperature assessment, 2014 was colder than 2013. In order to consider annual weather variations, a heating degree day sensitivity analysis was executed to normalize the effect of climate variations.

$115,872 86%
32% 32%
0,7 Year 73%
Greenhouse Gas
1 701 KG CO2 EQ 27%

Heating Electricity Consumption

This graph shows that for a same heating degree day, the electricity consumption is lower after the installation of the Demtroys System. Thus, less electricity is necessary to meet heating requirements. The difference between the two slopes gives the reduction in heating consumption rate which is 31.8%.


Gas Consumption

To be sure that the reduced electrical heating was not compensated by gas heating, a pre- and post-consumption
analysis was made. The results show that there is no significant difference in the consumptions and so that the
gas consumption was not affected by the retrofit.

Overall Thermal Comfort

One of Demtroys promises is that the tenant’s comfort is not compromised. To confirm this, a survey to investigate the tenants’ thermal comfort was conducted. One year after the heating management system was installed, a face-to-face survey has been done to obtain feedbacks from tenants. The survey has been conducted in 3 buildings, including the one studied: 2 buildings had an energy management system installed (B1 and B2) and one had not (B3). About 30% of the total tenants in each building answered. The constatations of this survey are that very little percentages of tenants reported either very cold or very warm thermal conditions during the heating seasons. All three buildings had very similar comfort responses. Several tenants were not aware of the new system and were informed about it during the survey.

For more details, contact us.
1 877 570-4272

This Project was partially funded by Canada Mortgage and Housing Corporation (CMHC) and Natural Resources Canada (NRCan) through their Program for Energy Research and Development (PERD).