Every new house in Ontario needs an EEDS form — the Energy Efficiency Design Summary — filed with the permit application. Designers charge $300 or more to complete one. This guide explains what SB-12 is, how the prescriptive packages work, and what goes on that form — so you can walk into the permit office knowing what your designer filled in and why.
Heating is the dominant energy use in Ontario homes, and space heating accounts for roughly 60% of a typical house's annual energy bill. The Ontario Building Code's energy efficiency requirements live in Section 12.2.1. of Division B — and they don't specify the technical requirements directly. Instead, Sentence 12.2.1.2.(3)(b) says the building shall conform to "Chapters 1 and 3 of MMA Supplementary Standard SB-12, Energy Efficiency for Housing." That supplementary standard is the document — called SB-12 — that does the actual work.
SB-12 has been through several editions. The current Ontario edition is based on the 2016 SB-12, with subsequent amendments incorporated into the 2024 compendium. The energy targets in the prescriptive packages are set to exceed, on a systemic basis, the previous 2012 Building Code requirements by 15%. In practical terms, an Ontario house built to SB-12 today uses significantly less heating energy than a house built in 2011 — largely because the R-value requirements for walls, ceilings, and basements went up, and because HRVs became mandatory.
SB-12 Clause 1.1.1.3.(1) gives three routes to compliance:
1. Prescriptive Compliance Packages (Section 3.1.1) — the lookup-table approach. Choose one of the pre-defined packages for your climate zone and heating system type. If every component in your building meets or exceeds the package requirements, you comply. No modelling software, no energy advisor. The designer fills in the EEDS form, checks the boxes, and that is your documentation. This is by far the most common path for standard Part 9 houses.
2. Performance Compliance (Section 3.1.2) — energy modelling. A qualified energy advisor runs HOT2000 or equivalent NRCan-recognized simulation software and shows that the proposed building's simulated annual energy use is not greater than a reference building designed to the applicable prescriptive package. This path is used for custom designs, buildings with high glazing ratios exceeding 22% of wall area, or cases where no prescriptive package can be met with the proposed envelope. It produces an EnerGuide Rating label and is required by many municipalities for incentive programs.
3. Other Acceptable Methods (Section 3.1.3) — Energy Star for New Homes Standard Version 12.6 or R-2000 certification both constitute compliance. If your builder is already pursuing one of these programs, your SB-12 compliance comes free with the certification documentation.
SB-12 divides Ontario into two climate zones at the 5,000 Heating Degree Day boundary (base 18°C). Zone 1 covers areas with fewer than 5,000 HDD — the vast majority of southern Ontario including Toronto (approximately 3,520 HDD), Ottawa (4,440 HDD), Hamilton, London, Windsor, Kitchener-Waterloo, Barrie, and Kingston. Zone 2 covers areas at 5,000 HDD or more — northern Ontario communities including Sudbury (approximately 5,150 HDD), Thunder Bay (5,520 HDD), Sault Ste. Marie (5,000 HDD), North Bay (5,080 HDD), and Timmins (approximately 5,900 HDD).
Zone 2 packages require meaningfully higher insulation levels and tighter mechanical equipment efficiencies than Zone 1, reflecting the roughly 30–60% more heating energy a Zone 2 house needs compared to a Zone 1 house with the same envelope. If you are unsure which zone applies to your project, the NRCan Canadian Climate Normals database lists HDD values by weather station, or your municipal building department can confirm the zone.
Each SB-12 table group contains six packages (numbered 1–6). The table groups are: Table A — for furnaces with AFUE of 92% or higher (the most common in Ontario new construction); Table B — for furnaces with AFUE of 84% to less than 92%; Table C — for buildings using electric space heating or heat pumps (4 packages in Zone 1, 2 packages in Zone 2).
Each package specifies minimum values for:
For each component, the table provides three equivalent representations — nominal R-value, effective R-value, and U-value — and you only need to meet one of the three. Most designers use nominal R from the product label.
The Energy Efficiency Design Summary is the supplementary permit form that documents SB-12 compliance. It has a simple structure: pick the compliance path (prescriptive package or performance modelling or Energy Star/R-2000), identify the climate zone, and for the prescriptive path, list the package number and the specified value for each component. The building inspector will spot-check the cross-section drawing against the EEDS values during framing inspection — if the insulation thicknesses in the wall section don't match the package specified on the EEDS, you get a hold on the inspection.
The EEDS is typically prepared by the designer (who holds a BCIN — Building Code Identification Number) or by the energy advisor. Designers charge $300–600 for a complete permit package including EEDS; standalone EEDS preparation for a straightforward prescriptive package is often $100–250. This tool generates a pre-design summary block that a designer can use as a starting point or that an experienced owner-builder can reference when completing the form themselves with a BCIN designer's oversight.
Continuous insulation is insulation applied without interruption across structural members — typically rigid foam board or mineral wool board on the exterior face of the wall sheathing, or spray foam on the interior warm side of the foundation wall. The "ci" designation in SB-12 package tables is not optional labelling — it is a specific performance requirement. A wall with R-22 cavity batts and no exterior foam does NOT comply with a package that says "R-19 + R-5 ci" even if the total numbers add to the same value. The reason is thermal bridging: wood studs at 16" o.c. conduct significantly more heat than the cavity insulation beside them, and continuous insulation on the exterior breaks that thermal bridge. R-5 of exterior foam adds the equivalent of R-7 to R-9 in effective assembly performance, even though its nominal rating is only R-5. For SB-12 compliance, the batt component and the ci component are checked separately — you must meet or exceed both.
Window performance is always stated as a U-value (the rate of heat flow through the assembly), while insulation is stated as R-value (the resistance to that flow). They are inverses: U = 1/R. A window labelled U-0.28 in Imperial units has an effective R of approximately R-3.6 for the whole assembly. SB-12 and NFRC both specify window performance as U-value because windows are composite assemblies — glazing, spacer, frame, and sash all conduct heat differently, and the NFRC 100 test procedure measures the whole assembly rather than any individual component. The common "double-glazed" or "triple-glazed" shortcuts are not precise enough for SB-12 compliance: a double-glazed window can range from U-0.48 (ordinary aluminum-frame unit) to U-0.28 (low-e argon with thermally broken frame). Always specify the NFRC-certified U-value on the permit drawings and confirm that the product the supplier ships matches. Energy Star Most Efficient designation in Zone A or B (Canadian climate zones) typically corresponds to U-0.21 or better.
One of the most common SB-12 compliance mistakes on sloped lots: SB-12 Sentence 3.1.1.1.(10) requires that for a dwelling unit with a walk-out basement, the thermal performance of the exposed basement wall shall be not less than that required for the above-grade wall if (a) the wall contains the door opening, or (b) the exposed wall area above ground level exceeds 50% of that basement wall area. This matters because the package requirements for above-grade walls (typically R-22 batt + R-5 ci or equivalent) are significantly higher than the typical basement wall requirements (typically R-20 ci alone). On a walk-out basement house, the south or east face of the foundation where the walk-out door is located must be insulated to the same standard as the above-grade wall — not the lower basement-wall standard. This frequently gets missed in the framing inspection because the foundation wall uses form-board or ICF designed to the lower basement-wall spec, and nobody upgraded the walk-out face.
The performance path (energy modelling) costs $800–2,000 in professional fees but unlocks real savings in some situations. The primary cases where it makes sense: (1) High glazing ratio — if your window area exceeds 22% of wall area, the prescriptive path is not available and you must model; (2) Unusual building geometry — a round house, an earth-sheltered design, or a house with very large exposed-slab floor area where the prescriptive tables don't cover the geometry well; (3) Trade-off optimization — performance modelling allows you to use a slightly lower-R wall in exchange for a slightly more efficient furnace, or vice versa. The code (Section 3.1.2.1.(6)) allows the envelope performance to be up to 25% below the reference package's envelope if the mechanical system compensates. This can reduce the cost of exterior rigid foam on a large house while still achieving compliance; (4) Incentive programs — Canada Greener Homes Grant, IESO initiatives, and many utility programs require an EnerGuide label, which only comes from performance-path modelling.
SB-12 Sentence 3.1.1.1.(16) states: "Ventilation systems serving dwelling units shall have a heat or energy recovery ventilator." There is no exception for well-insulated or airtight houses. The reason is that the same air-sealing measures that make a house energy-efficient also reduce natural ventilation — without an HRV, indoor air quality degrades from CO2, moisture, VOCs from building materials, and radon. The HRV is the mechanism that allows a well-sealed house to breathe without throwing away the heat in the exhaust air.
Sensible Recovery Efficiency (SRE) measures how much of that exhaust heat the HRV captures and transfers to the incoming fresh air, tested at 0°C per CAN/CGSB 149.10. An SRE of 75% means three-quarters of the heat in the stale outgoing air is pre-warming the fresh incoming air. SB-12 package requirements range from 65% to 81% SRE depending on the package — a 75% SRE HRV is the most common mid-tier product. High-performance HRVs achieving 81% or 85% SRE are available but cost $200–400 more. In Zone 2 (northern Ontario), the higher SRE requirement matters more because the temperature difference between indoor exhaust air and outdoor supply air is larger, so the heat recovery yield is proportionally greater.
This tool is a pre-design reference only. Every new residential building in Ontario requires a permit, and the permit application must include a completed EEDS form prepared by a qualified designer (BCIN) or professional engineer. The tool uses Imperial R-value and U-value units consistent with SB-12 IP tables. Verify all values against the current SB-12 and OBC 2024. Referenced clauses: OBC 12.2.1.2.(3)(b); SB-12 Sentences 1.1.1.3.(1), 3.1.1.1.(1), 3.1.1.1.(7)–(10), 3.1.1.1.(16)–(19), 3.1.1.2., 3.1.1.3., 3.1.2.1., 3.1.3.1.
Free Ontario SB-12 energy compliance checker. Enter your insulation R-values, window U-value, furnace AFUE, and HRV SRE to find which SB-12 prescriptive package your house meets — and generate an EEDS form summary. OBC 2024.
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