British Columbia · climate zone 4 · prices and rebates checked October 8, 2026

Insulation and upgrade payback calculator for Delta

Delta has 2,768 heating degree-days a year (climate zone 4), and NRCan recommends about R-45 in an attic here. For a typical detached house of about 1,600 sq ft (149 m²) built between 1966 and 1980 with a gas furnace, mid-efficiency, topping up the attic from R-20 to R-45 saves about $35 a year at $0.494/m³ and costs about $1,200–$1,960; the smallest open rebate that applies (BC Home Renovation Rebate) is $400. In an electrically heated house the same attic saves about $85 a year.

Heating degree-days

2,768

NBC climate zone 4

NRCan attic target

R-45

code minimum for new homes R-39.2

Natural gas, one more m³

$0.494/m³

used for every saving

Open rebate programs

1

BC Home Renovation Rebate

Upgrade payback calculator for Delta

Pre-filled for a typical 1966–1980 house in Delta with Delta's climate, prices and open rebates. The insulation levels are typical assumptions for the era, not measurements: change anything you know about your house. Nothing you enter leaves your browser.

Your house
Year built
Type
Size (heated floors above the basement)
sq ft
Heating and bills
$

Used for every saving (fixed charges left out).

$

Only used to turn a monthly bill into energy.

Calibrate to your bills (optional)

Based on a typical house

$380saved a year with 6 upgrades

About 770 m³ a year less for your gas furnace, mid-efficiency: 23.2 GJ of the 58.9 GJ of heat the house needs (39%).

Installed cost
$13,550–$21,460 + your quotes
Rebates counted
$1,900
Simple payback
58–98 years for the 4 upgrades with a cost
Saving over 20 years
$7,630

Enter your quote for wall insulation and basement wall insulation to add them to the cost and payback. The 4 upgrades with a cost save about $200 a year together.

Measures overlap, so the total (39% of your heating need) is less than the sum of each one alone (47%).

Add your annual use or a monthly bill to calibrate these numbers to your house. Most rebates need an EnerGuide evaluation before and after the work; their conditions are listed further down this page.

Attic insulation
R-
R-

NRCan recommends R-45 for climate zone 4; we cap the default at R-60. The building code minimum for a new house here is R-39.2.

sq ft
$
Or cost per sq ft (low – high)
$ – $

HomeStars (updated 21/08/2026): "installation costs range from $1.50 to $2.45 per square foot"; Canadian attic jobs average $1,500–$3,000 including materials and installation.

$35/yr · 2.1 GJ (3.6% of heating) · cost $1,200–$1,960 · $400 rebate · payback 23–45 years

Wall insulation
How
RSI

R-12

sq ft
$

We couldn't verify a 2025–2026 Canadian price for wall insulation, so this starts blank. NRCan: on an exterior retrofit the insulation is only about 15–20% of the cost.

$94/yr · 5.7 GJ (9.7% of heating) · cost enter your quote · $1,200 rebate · payback enter a cost

Basement wall insulation
RSI

R-4

RSI

R-20

sq ft
$

$150/yr · 9.0 GJ (15.3% of heating) · cost enter your quote · $1,200 rebate · payback enter a cost

New windows
windows
$
Or cost per window (low – high)
$ – $

HomeStars (updated 21/08/2026): $800–$1,000 for a double-hung and $900–$1,200 for a casement window, installed; bay and bow windows $2,500–$4,000.

$87/yr · 5.3 GJ (9.0% of heating) · cost $12,000–$18,000 · $1,500 rebate · payback over 100 years

Air sealing
%
ACH50

Leave the cut blank for our default: 20%, or 15% if your house tests under 4 ACH50. The blower-door number is on your EnerGuide report.

Cost (low – high)
$ – $

HomeStars (updated 21/08/2026): air sealing and ventilation "could add $350 to $1,500" to an attic insulation job.

$36/yr · 2.2 GJ (3.8% of heating) · cost $350–$1,500 · no rebate counted · payback 9.6–41 years

Thermostat setback
°C
hours a day
$

NRCan suggests 17 °C when you're asleep or away and 20 °C when you're home, and not going below 17 °C. $0 if you already have a programmable thermostat; we couldn't verify a 2025–2026 price for a new one.

$58/yr · 3.5 GJ (6.0% of heating) · cost $0 · no rebate counted · payback right away

Each upgrade on its own
UpgradeSaved a yearCost and rebatePayback20 years
Attic insulationR-20 → R-45 over 800 sq ft $3570 m³ a year $1,200–$1,960rebate $400 23–45 years $690
Wall insulationR-10 exterior insulation: RSI 2.1 → 3.9 over 1,580 sq ft $94190 m³ a year your quoterebate $1,200 enter a cost $1,880
Basement wall insulationRSI 0.7 → 3.5 over 890 sq ft of wall $150300 m³ a year your quoterebate $1,200 enter a cost $2,980
New windows15 windows: U 2.86 → 1.22 $87175 m³ a year $12,000–$18,000rebate $1,500 over 100 years $1,740
Air sealingA 20% cut in air leakage (NRCan: about 25% of heat loss) $3674 m³ a year $350–$1,500 9.6–41 years $730
Thermostat setback3.0 °C lower for 8 hours a day $58120 m³ a year $0 right away $1,160

Savings use the price of one more unit of energy, not your average price. Each upgrade is shown on its own against your house as it is now; the total above accounts for overlap. Payback = (cost − rebate) ÷ yearly saving; the 20-year figure has no price increases or discounting.

Delta at a glance: standard upgrades for a 1966–1980 house

Detached, about 1,600 sq ft over a full basement, two storeys, with the era's typical insulation (attic R-20, walls RSI 2.1, uninsulated basement walls, double-glazed windows). Savings use the price of one more unit of energy; costs are installed ranges where we could verify one.

Gas-heated (mid-efficiency furnace)
UpgradeSaved a yearCost and rebatePayback20 years
Attic insulationR-20 → R-45 over 800 sq ft $352.1 GJ · 3.6% $1,200–$1,960rebate $400 23–45 years $690
Wall insulationR-10 exterior insulation: RSI 2.1 → 3.9 over 1,580 sq ft $945.7 GJ · 9.7% get a quoterebate $1,200 enter a cost $1,880
Basement wall insulationRSI 0.7 → 3.5 over 890 sq ft of wall $1509.0 GJ · 15.3% get a quoterebate $1,200 enter a cost $2,980
New windows15 windows: U 2.86 → 1.22 $875.3 GJ · 9.0% $12,000–$18,000rebate $1,500 over 100 years $1,740
Air sealingA 20% cut in air leakage (NRCan: about 25% of heat loss) $362.2 GJ · 3.8% $350–$1,500 9.6–41 years $730
Thermostat setback3.0 °C lower for 8 hours a day $583.5 GJ · 6.0% $0 right away $1,160
Electrically heated (baseboards)
UpgradeSaved a yearCost and rebatePayback20 years
Attic insulationR-20 → R-45 over 800 sq ft $852.1 GJ · 3.6% $1,200–$1,960rebate $400 9.4–18 years $1,710
Wall insulationR-10 exterior insulation: RSI 2.1 → 3.9 over 1,580 sq ft $2305.7 GJ · 9.7% get a quoterebate $1,200 enter a cost $4,640
Basement wall insulationRSI 0.7 → 3.5 over 890 sq ft of wall $3659.0 GJ · 15.3% get a quoterebate $1,200 enter a cost $7,330
New windows15 windows: U 2.86 → 1.22 $2155.3 GJ · 9.0% $12,000–$18,000rebate $1,500 49–77 years $4,290
Air sealingA 20% cut in air leakage (NRCan: about 25% of heat loss) $902.2 GJ · 3.8% $350–$1,500 3.9–17 years $1,790
Thermostat setback3.0 °C lower for 8 hours a day $1453.5 GJ · 6.0% $0 right away $2,870

The house needs about 58.9 GJ of heat a year here. Walls in this era already hold about RSI 2.1, so dense-packing gains nothing and the table shows R-10 of exterior insulation instead. Wall and basement prices start blank because we couldn't verify a 2025–2026 Canadian cost; the 20-year column shows what each upgrade is worth to compare with a quote.

Rebates for these upgrades in British Columbia

Market-rate rebates come from the Home Renovation Rebate Program. Insulation, windows and doors are open to most heating fuels. In our 13 BC cities, heat pump rebates are mainly for electrically heated homes; FortisBC gas customers can get $4,000 for a dual-fuel system (a heat pump paired with a gas furnace, replacing a furnace at least 15 years old), and full switches from gas, propane or oil are paid only in northern BC (100 Mile House and north) unless the household is income-qualified. The requirements changed for invoices dated on or after October 15, 2026, so confirm amounts before you buy.

Attic insulation

BC Home Renovation Rebate Open
Attic—flat and cathedral ceiling: $0.02 x R-value added x sq ft; minimum R12 added; rebate maximum $900.
Conditions: Rules for invoices dated May 15 to October 14, 2026 (new requirements apply from October 15, 2026; confirm the current amount). Year-round primary residence at least 12 months old (detached, secondary suite, mobile on foundation, individually metered duplex/triplex/row/townhome or small multiplex); condos and apartments excluded. Home primarily heated by BC Hydro, FortisBC or eligible municipal electricity, FortisBC/Pacific Northern Gas natural gas or pipe-propane, tank propane or oil (wood-heated homes only qualify for a heat pump water heater). Licensed…
Deadline: Apply within 6 months of invoice.
official page ↗ · checked October 8, 2026

Wall insulation

BC Home Renovation Rebate Open
Exterior wall cavities: $0.09 x R-value added x sq ft (minimum R12 added), maximum $1,200. Exterior wall sheathing: $0.09 x R-value added x sq ft (minimum R3.8 added), maximum $1,200.
Conditions: Rules for invoices dated May 15 to October 14, 2026 (new requirements apply from October 15, 2026; confirm the current amount). Year-round primary residence at least 12 months old (detached, secondary suite, mobile on foundation, individually metered duplex/triplex/row/townhome or small multiplex); condos and apartments excluded. Home primarily heated by BC Hydro, FortisBC or eligible municipal electricity, FortisBC/Pacific Northern Gas natural gas or pipe-propane, tank propane or oil (wood-heated homes only qualify for a heat pump water heater). Licensed…
Deadline: Apply within 6 months of invoice.
official page ↗ · checked October 8, 2026

Basement wall insulation

BC Home Renovation Rebate Open
Basement/crawlspace walls: $0.09 x R-value added x sq ft (minimum R10 added), maximum $1,200. Other (exposed floor, floor over crawlspace, basement header): $0.07 x R-value added x sq ft (minimum R20), maximum $1,000. One rebate for basement/crawlspace walls or floor over crawlspace.
Conditions: Rules for invoices dated May 15 to October 14, 2026 (new requirements apply from October 15, 2026; confirm the current amount). Year-round primary residence at least 12 months old (detached, secondary suite, mobile on foundation, individually metered duplex/triplex/row/townhome or small multiplex); condos and apartments excluded. Home primarily heated by BC Hydro, FortisBC or eligible municipal electricity, FortisBC/Pacific Northern Gas natural gas or pipe-propane, tank propane or oil (wood-heated homes only qualify for a heat pump water heater). Licensed…
Deadline: Apply within 6 months of invoice.
official page ↗ · checked October 8, 2026

Air sealing

No air sealing rebate in the Home Renovation Rebate requirements for invoices dated May 15 to October 14, 2026; check the October 15 update.

Windows and doors

BC Home Renovation Rebate Open
Tier 2 window/door: $100 each; U-Factor 1.22 W/m²-K or less; rebate maximum $2,000.
Conditions: Rules for invoices dated May 15 to October 14, 2026 (new requirements apply from October 15, 2026; confirm the current amount). Year-round primary residence at least 12 months old (detached, secondary suite, mobile on foundation, individually metered duplex/triplex/row/townhome or small multiplex); condos and apartments excluded. Home primarily heated by BC Hydro, FortisBC or eligible municipal electricity, FortisBC/Pacific Northern Gas natural gas or pipe-propane, tank propane or oil (wood-heated homes only qualify for a heat pump water heater). Licensed…
Deadline: Apply within 6 months of invoice.
official page ↗ · checked October 8, 2026

Caps and bonuses

$20 per percentage improvement in EnerGuide rating (GJ/year), minimum $750 up to $2,000. At least three bonus-eligible upgrades and a post-upgrade EnerGuide evaluation within 18 months of the pre-upgrade evaluation; apply within 6 months of the post-upgrade evaluation. source ↗

$300 for two bonus-eligible upgrades installed within 18 months of each other; one Two Upgrade Bonus or Home Energy Improvement Bonus per home. Insulation counts if a location earns at least $500; windows/doors if at least $250. source ↗

Financing

FortisBC heat pump loan Open
Up to $6,500; 1.9% official page ↗

Common questions in Delta

Does attic insulation pay for itself in Delta?

For a typical detached house of about 1,600 sq ft (149 m²) built between 1966 and 1980, going from R-20 to R-45 saves about $35 a year with a mid-efficiency gas furnace and $85 with electric baseboards, counted at the price of one more unit of energy. At HomeStars' $1.50–$2.45 per sq ft (about $1,200–$1,960) and a $400 rebate, simple payback is 23–45 years (9.4–18 years for an electrically heated house). Attics with less than R-20 save more.

What insulation rebates are open in Delta?

As of October 8, 2026: Attic insulation: BC Home Renovation Rebate (Attic—flat and cathedral ceiling: $0.02 x R-value added x sq ft; minimum R12 added; rebate maximum $900.) Wall insulation: BC Home Renovation Rebate (Exterior wall cavities: $0.09 x R-value added x sq ft (minimum R12 added), maximum $1,200) Basement wall insulation: BC Home Renovation Rebate (Basement/crawlspace walls: $0.09 x R-value added x sq ft (minimum R10 added), maximum $1,200). Conditions apply (most need an EnerGuide evaluation before the work); the calculator counts the smallest amount for each and lets you switch it off.

How much insulation should an attic have in Delta?

NRCan's Keeping the Heat In recommends about R-45 (RSI 7.9) for an attic in climate zone 4, which covers Delta at 2,768 degree-days. The National Building Code minimum for a new house here is R-39.2 without a heat recovery ventilator. Our calculator caps its default target at R-60.

Are new windows worth it for energy savings in Delta?

Rarely on energy alone. Replacing 15 double-glazed windows with ENERGY STAR models saves about $87 a year in a gas-heated house and $215 with electric heat, against $12,000–$18,000 at HomeStars' $800–$1,200 a window: payback over 100 years. Replace windows when they fail or for comfort; air sealing and attic insulation pay back much faster.

How much do air sealing and a thermostat setback save in Delta?

Cutting air leakage by 20% saves about $36 a year in a typical gas-heated house here (NRCan: about a quarter of heat loss is air leakage), and turning the thermostat down 3 °C for 8 hours a night saves about $58 a year (NRCan: about 2% per degree over eight hours). Heat pumps should be set back no more than 2 °C.

How we calculate this

1. Heat saved by insulation and windows

heat saved (GJ/yr) = area × (1/RSI before − 1/RSI after) × 2,768 degree-days × 86,400 s ÷ 10⁹ × F

F is a conservative factor: 0.75 above grade (the sun, people and appliances supply some heat, and no installation is perfect) and 0.4 for basement walls (most of the wall is below grade, where the ground stays far warmer than winter air). Windows use U-values instead of 1/RSI.

2. Typical starting points

  • Attic: R-12 before 1966, R-20 (1966–80), R-28 (1981–95), R-40 (1996–2010), R-50 (2011+). Target: NRCan's retrofit recommendation for climate zone 4, capped at R-60.
  • Walls: RSI 0.7 (empty, before 1946), 1.4 (1946–65), 2.1 (1966–95), 3.0 (1996–2010), 3.4 (2011+). Dense-packing a 2×4 cavity gives about RSI 2.1 (cellulose is RSI 0.63 per 25.4 mm, NRCan Table 3-1); R-10 of exterior insulation adds RSI 1.76.
  • Basement walls: RSI 0.7 before 1981 (bare concrete plus the soil against it), 2.1 for 1981–2010, 3.5 since; target RSI 3.5 (R-20).
  • Windows: 12% of floor area (1.2 m² each), single with storm before 1966, double clear 1966–95, double low-e after.

These starting values are AuditYourHome planning assumptions for a typical house of each era, not survey results: we could not verify a Canadian table of insulation levels by year built. Change them to match your house; an EnerGuide evaluation measures them.

3. Air sealing

Without a blower-door number we use NRCan's statement that typically about 25% of heat loss is air leakage: saving = 25% × reduction × heating need × 0.75. With your EnerGuide result (ACH50), everyday leakage is ACH50 ÷ 20, near the conservative end of the 10–25 range used in the field, and:

heat saved = drop in natural air changes × house volume × 1.21 kJ/m³·°C × degree-days × 24 ÷ 10⁶ × 0.75

We assume a 20% reduction (15% if the house is already under 4 ACH50); rebate programs pay for measured cuts of 10%, 20% and 30%.

4. Thermostat setbacks

NRCan: “A drop of 1°C (2°F) over an eight-hour period can save about 2 percent on your heating energy consumption.” Saving = 2% × degrees × hours ÷ 8. Heat pumps are limited to a 2 °C setback, NRCan's advice, because deep setbacks can bring on backup heat.

5. Caps, overlap and your bills

No single measure may save more than 35% of the heating need, and all of them together no more than 60%. Measures overlap (a better attic leaves less heat for new windows to save), so the combined saving is 1 − (1 − a)(1 − b)…, always less than the simple sum. If you enter bills, every saving is scaled by how your use compares with a typical house (between 0.5× and 1.6×).

6. Dollars, rebates and payback

payback (years) = (installed cost − rebate) ÷ yearly saving at the price of one more unit of energy

Rebates use each program's lowest published amount per unit (per home, per window, per sq ft or per sq ft × R-value added), only for programs open today and only where your heating fuel qualifies; you can switch each one off. The 20-year saving is the yearly saving × 20, with no price inflation or discounting. Where we could not verify a 2025–2026 installed cost (walls, basements, exterior insulation), the cost starts blank: enter your quote.

More for Delta

Heating and hot water costs in DeltaWhat heating, hot water and air conditioning cost at your local prices, and what each heating system would cost instead.Home health check in DeltaRadon results, winter humidity and window condensation, smoke and CO alarm rules, well water and mould.Appliance running costs in DeltaWhat your fridge, dryer, freezer and other appliances cost to run at your local electricity price, and what a newer model saves.
Build your upgrade plan → All home services in Delta Home energy audits in DeltaAttic insulation inspections in DeltaBlower door tests in DeltaThermal imaging in Delta British Columbia rebates and programs

Sources

Prices and programs checked October 8, 2026. Climate: NRCan HOT2000 (Vancouver International) for heating and ECCC 1981–2010 normals (Richmond Nature Park) for cooling and temperatures.

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