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title: "The CleanBC '80% Rule': What Counts as Whole-Home Heat Pump Heating (And What Voids Your Rebate)" description: "ESP requires your heat pump to serve as primary heat for at least 80% of the conditioned space. Here's what that actually means for ductless, dual-fuel, and wood stove setups in BC." slug: cleanbc-80-percent-rule-whole-home-heat-pump publishedAt: 2026-04-26 category: rebates

The CleanBC "80% Rule": What Counts as Whole-Home Heat Pump Heating (And What Voids Your Rebate)

The CleanBC Energy Savings Program rebate rules contain one short phrase that decides whether a $5,000 baseboard-conversion rebate or a $16,000 fuel-switch rebate actually pays out: the heat pump must "serve as primary for 80% of the conditioned space." Most Nelson homeowners getting quotes never see that line. Most contractors don't volunteer it. And it's the single most common reason a properly-installed heat pump gets denied at the rebate stage.

This is the rule, what it actually means, and the install configurations that quietly fail it.

The actual rule, in plain language

ESP and HRR both require the heat pump to be the primary heating source for the home — not a supplemental zone, not a comfort upgrade. The rebate rules database states the heat pump must serve as primary heat for at least 80% of the conditioned floor area, with a minimum capacity of 12,000 BTU and NEEP-listed cold-climate performance. A CSA F280 heat loss calculation is required, and that document is what a program reviewer uses to decide whether the install meets the bar.

"Conditioned space" means heated square footage. Garages, unfinished crawlspaces, and unheated attics don't count. A 2,000 sq ft Nelson bungalow with 1,800 sq ft of conditioned space needs a heat pump sized to do the primary heating work for at least 1,440 sq ft.

"Primary" means capacity-sized to do most of the work at design temperature — not just sized to take the easy hours. In Nelson's design temperature of -20 to -25°C, the heat pump's heating capacity at that outdoor temperature must cover roughly 80% of the home's heat loss at the same outdoor temperature. A unit that carries the shoulder season but tags out to baseboards every January night is a supplemental system, not a primary one.

HRR uses a looser version of the same idea: a "whole-home" HRR rebate ($4,000) requires 100% of heating coverage at -5°C, and a "partial-home" rebate ($2,000) covers a system that handles 50%+ of heat. ESP collapses both into one tier and demands the higher 80%-at-design-temperature standard. There is no partial-home ESP rebate. You qualify for the full amount or get nothing.

Why the rule exists

The province is paying up to $16,000 per household to switch heating systems. It's not paying that to add a heat pump as bedroom AC. A heat pump handling 30% of the work while baseboards or a gas furnace cover 70% doesn't materially reduce annual emissions or electrical load enough to justify the rebate, and the program filters those installs out at the application stage rather than chasing them with audits afterward.

This is why the F280 heat loss calculation is non-negotiable — it's the mathematical proof that the equipment selected meets the 80% bar. ClearResult, the ESP administrator, reads it. Technical specifics in the F280 heat loss calculations explainer.

The configurations that quietly fail

Five common Kootenay setups land in the gray zone. Three of them fail the rule outright. Two pass but only with deliberate sizing.

1. Single-head ductless mini-split in a multi-room home

The most common failure. A homeowner with electric baseboards across a 1,500 sq ft home installs one 12,000 BTU wall-mounted head in the living room. The head heats the living room. The bedrooms with closed doors stay on baseboards. That heat pump covers maybe 600 sq ft — 40% of conditioned space.

ESP fails it. HRR may pay the partial-home $2,000 if the contractor can argue 50%+ coverage at -5°C, but the whole-home $4,000 is gone and ESP's $5,000 was never on the table.

The fix: size the system to actually heat the bedrooms — multi-head ductless (one outdoor unit, three or four indoor heads) or ducting the unit through existing or new ductwork. We walk through the choice in single-zone, multi-head, or ducted heat pump.

2. Two heads in main rooms, baseboards retained as primary in bedrooms

Better than scenario one, often still short of 80%. A two-head system covering 900 of 1,500 conditioned sq ft is at 60%. Reviewers ask: at design temperature, can the heat pump physically heat those baseboard rooms? If air can't push through closed doors and cold hallways, it's a supplemental install. The fix is ducting, or adding a third or fourth head into the bedrooms — usually $4,000–$8,000, which is the difference between $0 and $5,000–$16,000 in rebates.

3. Heat pump plus retained gas furnace (dual-fuel hybrid)

This used to be its own program. FortisBC's dual-fuel rebate ended December 18, 2025 with no successor — verify before quoting any dual-fuel-specific path. A dual-fuel install in 2026 is now ESP-or-nothing, and ESP only funds it if the heat pump is sized as the primary heater for 80%+ of conditioned space, with the gas furnace as backup (locked out above roughly -10 to -15°C).

The configuration that fails: heat pump sized for 50% of design load, gas furnace doing the real work on cold days. The configuration that passes: cold-climate heat pump sized to carry the home down to -20°C with the furnace locked out except for emergency backup. The F280 has to reflect that split.

4. Heat pump plus wood stove (the Kootenay default)

The reassuring scenario. Wood stoves don't break the 80% rule — it measures what's installed as mechanical primary heat, not how often a secondary appliance runs. A heat pump sized for 80%+ of conditioned space passes ESP even if the homeowner burns wood every night from October to April.

The catch: the F280 should not assume the wood stove carries part of the design load. Sizing small on the assumption that "the stove picks up the slack at -20°C" produces an undersized system on paper and in reality. Full pattern in heat pump and wood stove in Kootenay homes.

5. Baseboards retained as backup only

Allowed. ESP doesn't require baseboard removal — it requires that the heat pump can do the primary heating job. Keeping baseboards as emergency backup is fine, but the thermostat needs proper lockout configuration so resistance heat doesn't quietly run every morning during defrost cycles or setback recovery. Misconfigured backup is the #1 cause of "my heat pump bills are higher than my baseboards" — covered in the most common heat pump rebate mistakes.

How sizing decides whether you pass

"I'll just ask my contractor for a bigger unit to be safe" is the wrong instinct. Oversizing causes short-cycling, reduced seasonal efficiency, and accelerated compressor wear. The right answer is F280-sized at design temperature, not biggest-quote-wins.

The number that matters on a spec sheet isn't the nameplate BTU rating — it's the heating capacity at -15°C and -20°C in the NEEP cold-climate database. A 24,000 BTU unit may deliver only 14,000 BTU at -20°C, and that's the number the F280 needs to clear the 80% bar.

For Nelson's -20°C design temp:

• A 1,200 sq ft 1970s home with average insulation: heat loss roughly 24,000–28,000 BTU/hr at -20°C
• An 1,800 sq ft 1950s home with poor insulation: 40,000–48,000 BTU/hr
• A well-insulated 2,200 sq ft 2010s home: 32,000–36,000 BTU/hr

The heat pump's -20°C capacity needs to cover 80%+ of those numbers. Brochure SEER and HSPF2 ratings are summer-day numbers and don't get you across the line.

When this actually surfaces

Pre-application review by ClearResult. The reviewer compares the F280's calculated design-temperature heat loss against the heat pump's NEEP-rated capacity at the same temperature. A mismatch flags the application — usually after the install is complete and paid for.

Post-install audit. ESP audits a sample of approved installs and can claw back rebates if the system is undersized. Rare, but it happens.

Energy Advisor flag during EnerGuide evaluation. If the homeowner is also pursuing HomeSave Central Kootenays — which requires pre- and post-retrofit EnerGuides — the advisor can flag a system that won't deliver modeled savings. This doesn't affect ESP directly, but it does affect the HomeSave performance rebate, which pays on measured kWh reduction.

ESP versus HRR on this requirement

	ESP	HRR (whole-home)	HRR (partial-home)
Coverage threshold	Primary for 80% of conditioned space at design temp (~-20°C)	100% of heating at -5°C	50%+ of heating at -5°C
Rebate amount	$5,000 (electric→HP) / $10,500–$16,000 (fuel switch)	$4,000	$2,000
F280 required	Yes	Yes	Yes
Min capacity	12,000 BTU	12,000 BTU	Not specified
NEEP cold-climate listing	Required	Required	Recommended

ESP is the more demanding bar by a meaningful margin. A system that passes HRR's whole-home test (100% coverage at -5°C) doesn't automatically pass ESP's primary-for-80%-at-design-temp test, because Nelson's design temp is closer to -20°C, where heat pump capacity is significantly degraded. We compare the two programs end-to-end in ESP versus HRR.

What to ask your contractor before you sign

Five questions. If the contractor can't answer any of them in writing, push back before putting down a deposit.

1. "What's the F280 design heat loss for my home at -20°C, and the heat pump's NEEP-rated heating capacity at the same temperature?" Two specific numbers. The first divided by the second should be ≤ 1.25 — the heat pump covers at least 80% of design load.

2. "What percentage of my conditioned floor area will this system serve as primary heat?" Should be ≥ 80%, with each room accounted for. "The bedrooms will get some passive heat" is not the answer.

3. "At what outdoor temperature does the backup heat lock out?" Backup resistance heat (or a retained gas furnace) should be disabled above a specified outdoor temperature. -10 to -15°C is typical for cold-climate units in the Kootenays.

4. "Is this equipment on the NEEP cold-climate database, and at what capacity does it run at -25°C?" NEEP (Northeast Energy Efficiency Partnerships) is the cold-climate certification ESP references. Off-list equipment creates application friction.

5. "Have you submitted ESP applications with this exact equipment configuration before, and have any been denied?" A contractor who has run installs through the program knows which combinations clear review.

The contractors who can't answer are usually the same ones who skip the F280 and quote off rule-of-thumb sizing. Longer checklist in contractor vetting questions for Nelson.

FAQ

Does the 80% rule apply if I'm replacing electric baseboards with a heat pump?

Yes. The rule is the same regardless of what you're switching from. The ESP electric-to-heat-pump rebate ($5,000 at Levels 1 and 2) requires primary heating coverage of 80% of conditioned space at design temperature, just like the fuel-switch rebate. Single-head mini-splits in multi-room homes are the most common failure mode for baseboard conversions specifically.

Can I keep the wood stove and still qualify?

Yes. The 80% rule measures what the heat pump is mechanically capable of, not how often you use it. A wood stove is a secondary appliance and doesn't reduce the heat pump's qualifying coverage as long as the F280 sizing doesn't depend on the stove carrying part of the design load.

What if my F280 says the heat pump covers 75% of conditioned space?

You're below the bar. Options: upsize the heat pump, add a head or zone to extend coverage, or improve envelope (insulation, air sealing) to reduce the home's design load enough that the existing system covers a higher percentage. Insulation-first is sometimes the cheaper path because it stacks its own ESP rebate on top.

Does HRR's "whole-home" rebate use the same 80% definition as ESP?

No. HRR's whole-home test is "covers 100% of heating at -5°C," which is a much milder day than Nelson's -20°C design temperature. A system that passes HRR whole-home doesn't automatically pass ESP. ESP is the stricter standard.

Will my contractor catch this if they don't do a proper F280?

Probably not. That's the point. A "rule of thumb" sizing approach (BTU per square foot multipliers) doesn't produce the documentation the program reviewer needs, and a contractor who doesn't run the calculation has no way of knowing whether the equipment they're proposing actually meets the 80% bar. The F280 is what makes the math visible — and what makes the rebate defensible.

What happens if the rebate is denied after install?

For ESP, denial happens at application review — after the install is paid for, before the rebate disburses. There's no provincial appeal for sizing-based denials. The fallback is HRR's whole-home or partial-home rebate, if the system meets that lower bar (it usually does).

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The 80% rule isn't a regulatory accident. It's the program enforcing the difference between an install that materially changes how a home is heated and one that decorates an existing system with a comfort upgrade. The province pays for the first kind. Knowing where that line falls — before the contractor's truck arrives — is the difference between $0 and the full rebate.