Climate Region and Building Science
Identify your climate region and know the heating degree days (“HDDs”) to accurately model heat losses.
Building science is what energy professionals use to understand how the house works as a system and is focused on controlling three key issues: heat, air, and moisture flow. Improving the performance of a house in any one area impacts all these factors and can have a major influence on occupant health and safety, the durability of the structure, and its greenhouse gas emissions. The building envelope needs three key items to perform well from a building science perspective:
- A completely insulated building envelope, controlling heat flow;
- A continuous air barrier, controlling air flow;
- A vapour barrier, controlling moisture flow.
These three items are crucial in each climate region and depending on the project location, you may find varying building practices. Careful design and implementation of these integral systems is required to create a high-performance home.
For more information on identifying your climate region and further understanding building science principals, please refer to “Keeping the Heat In” provided by NRCan’s Office of Energy Efficiency.
This is the start of a NZE or DER retrofit project. An NRCan certified EA carries out a site visit and a blower door test. A blower door test determines the airtightness of the home. While this provides good baseline information, an NZE or DER project requires much more data in order to accurately plan a suite of energy-saving upgrades. Including but not limited to:
- A homeowner interview should be performed to determine occupant energy use (lights, appliances, electronics, etc.).
- Historic energy bills must be gathered and compared against weather data, and home occupancy levels to provide a clear picture of the home’s existing conditions.
- Energy monitoring equipment is installed at the home during the initial stages of the project. Energy monitoring equipment allows the service organization to obtain accurate and detailed energy consumption than energy bills provide, helping to make informed decisions towards energy conservation recommendations, monitor upgrade results and determine actual payback.
Renewable Energy Resource Assessment
A renewable energy contractor or other qualified 3rd party consultant should be hired to assess the potential for the installation of a renewable energy system on-site. This assessment should explore the maximum amount of energy that can be generated at the home. On-site generation can be attained through solar PV, wind, micro-hydro or a combination. Careful consideration should be given to barriers that can be moved and removed (tree clearing/topping options, water diversion and existing buildings) to ensure maximum energy generation. Choosing the final size of the renewable energy generation system will happen later in the process as the energy conservation and efficiency upgrade pathway is created and modelled. The cost of installing a larger solar PV system should be compared against the cost of additional upgrades to the building. Solar PV is easily scalable and often leads to a better return on investment compared to upgrades that can be grouped with deferred maintenance such as exterior insulation, siding and window replacements.
In Nova Scotia, a preliminary solar assessment can be performed online using Solar Assist. Other options may be available to you if you are in a different province or territory.
Create the NZE/DER Plan
Once all the information about a home has been collected, a phased NZ/DER plan is developed by the Project Manager who determines energy savings, costing, and ROI of the proposed upgrades. The plan should align with the homeowner’s goals and offer optimal financial returns and long-term durability of the proposed upgrades. A phased approach must be taken, grouping or bundling work whenever possible to maximize cost-effectiveness and ensure occupant health, safety, and comfort. Often, energy savings from the early upgrade phases can help to pay for additional upgrades in later phases.
Leverage Existing Programs & Services
Help homeowners find and apply for rebates in their area to maximize cost effectiveness of upgrades and provide the homeowners with more incentive to move closer towards the NZE goal.
Click here for more information on financing options available within Nova Scotia.
Click here to see financial incentives currently available by province, compiled by NRCan.