Energy Code 9.36 – Where Do Windows and Doors Fit in?

Section 9.36 of the National Building Code details new requirements for housing and small buildings that is focused on improving the energy efficiency and reduction of greenhouse gas emissions. The code references six climate zones. The prairies have four of these zones. The specific weather location may be determined by referencing Appendix C of Division B in the Code or by consulting the local authority.

Compliance Map

Compliance Paths

Energy Code 9.36 includes three paths for compliance; Prescriptive, Trade-Off, and Performance Compliance. Select only one compliance path; multiple compliance paths are not permitted on a single building.

Prescriptive Path – The acceptable level of building energy efficiency by constructing the minimum requirements. This path involves following the prescriptive requirements of Subsection 9.36.2, 9.36.3 and 9.36.4 and is typically the simplest compliance path. It involves meeting all requirements in that part, but might not be appropriate for all buildings.

Prescriptive / Trade off Path – The acceptable level achieved by swapping of one or more building envelope thermal performance requirements, resulting in no worse thermal performance than if the affected assemblies met prescriptive requirements. If you need more flexibility in your design, a trade-off path allows you to trade elements within the above ground building envelope to demonstrate an equivalent level of performance without meeting every prescriptive requirement.

Performance Path – The acceptable level by employing a computer simulation software or calculations to compare a proposed design with a hypothetical reference building to show that the proposed design will use less energy over the course of an operational year. Once construction of the house is complete, a blower door test is performed and a Natural Resources Canada EnerGuide Rating System label is issued.

How do windows and door fit into Energy Code 9.36?

The Code allows windows and doors to qualify under two different energy performance rating methods: by the total unit U-value, and by Energy Rating (ER).

The U-value is the rate of heat loss through windows under standardized winter conditions and does not take solar heat gain into account. The ER is an overall energy balance rating that takes account of passive solar heat gain in addition to heat loss.

The ER is intended for use in homes with average window-to-wall ratios, and an approximately even distribution of windows on all sides of the home, and no external window shading devices. In such homes it has been shown to be more effective for selecting windows for lowest year round energy use. The ER is not recommended for homes with higher window-to-wall ratios (above 30%), or with windows facing primarily one or two orientations. Under these conditions occupants could face heating discomfort, or fail to obtain the benefits of moderate passive solar heat gain.

For homes with high window to wall ratios, or windows primarily facing one or two orientations, windows should be selected on the basis of U-value, and with consideration to reduce occupant discomfort from excessive solar heat gain by use of external shading or glass with lower solar heat gain.

There is some flexibility that allows trade-offs, in which a better performing window or glass door can compensate for a worse-performing product having the same orientation. It also has a performance path, and it is possible that homes designed under the performance path could accommodate several products that have worse than prescriptive ratings. The code also relaxes the U-value requirement for one door in a home. The intent is to allow decorative or heritage style entrance doors to be used which might be constructed of materials that cannot achieve the prescriptive U-values.

This table provides the maximum U-value and minimum Energy Rating for your building zone.


Determining your Durabuilt window and door Performance Class

As a basic reference guide, take a look at our Durabuilt Energy Performance info sheet that provides single unit window performance information. For more complete information based on your particular window and door configurations contact us to get a quote that contains specific energy performance information for every window and door.

The code requires products to be labeled with energy performance ratings. This ensure your windows or doors comply with the energy requirements based on your site location.

To obtain more detailed information feel free to book a consultation or get a quote from a Durabuilt sales consultant or dealer partner.

What Is The Difference Between Full Frame And Box Frame Renovations?

In some situations where it is important for the customer to preserve historic characteristics of the home, we may be able to leave existing wood frames and simply replace it with a window insert. This depends on the state of existing windows and frames. Nine times out of ten, our recommendation is a full frame renovation where you remove any rotted wood and poorly performing components to replace the entire window system with a new high performance window.

Are your installers sub-contractors?

Durabuilt install crews are owner-operators that run their own crews, but it is a requirement that they exclusively work with Durabuilt Windows & Doors and our products. Extensive training and product knowledge is a requirement and expectation from members of the install team. Take comfort in knowing that the average installer for Durabuilt has been with us for 3+ years and has have a background in window and door renovations. Because we have a very low turnover rate, our installers take pride in their work and are passionate about Durabuilt and our customers.

How Long Will My Renovation Take?

Durabuilt Windows & Doors’ skilled installers can complete most renovations within one or two days, and full home packages in three days or less. During the renovation you can expect a clean and safe worksite where drop cloths are used to catch excess debris. Tools and garbage will also be removed and collected nightly.

What sort of budget do I need to replace all my windows and doors?

Several variables come into play when it comes to replacing your windows and doors. This includes the age of your home, condition of your windows, water and other damage, and if you are making any design changes to the shape and openings of your windows and doors. During your free in-home estimate, your Durabuilt Sales Consultant will run through all the necessary steps and questions to best recommend and quote your project. Remember that Durabuilt offers products for every budget, and you can renovate at your own pace starting with a few windows and doors first.

Why should I renovate with Durabuilt?

Durabuilt Windows & Doors is a local Edmonton based company that employs over 400 staff members. We are a CSA Certified manufacturer and Energy Star partner. We have over 25 years experience and back our products with a competitive warranty and local service teams. As a family-run business, we value our customer’s satisfaction and pride ourselves on providing quality products at a competitive price.


  • No categories

Recent Posts