Propane is a workhorse fuel: it fires up weeknight BBQs, takes the edge off shoulder-season evenings with patio heaters and fire tables, keeps showers hot, dries laundry, heats pools and garages, and—when the grid falters—keeps the lights on with standby generators. If your home relies on propane and you’ve ever wondered, “How long will my tank last?” or “What should I budget this season?”, this guide is for you.
Below you’ll find a simple, reliable way to estimate propane usage for every common appliance (outdoor and indoor), plus smart tactics to stretch your fuel, size the right tank, and avoid surprise bills.
The One Formula You Need
Everything starts with a constant: one U.S. gallon of propane contains ~91,452 BTUs of energy. That number comes from the U.S. Energy Information Administration and is the industry standard for calculations. Although we don’t typically use gallons in Canada, the standard size of propane tanks we use for grills is based on the American 5-gallon/20 lb tank.
From that, you can build a quick, repeatable estimate:
Propane used (gallons) = (Appliance BTU rating × hours used) ÷ 91,452
- If your appliance lists kBTU/h, multiply by 1,000 first.
- In Canada, you often buy propane by the litre. For a rough conversion: 1 U.S. gallon = 3.785 litres. If you prefer to think in litres, divide the gallons result by 3.785.
- A standard 20 lb BBQ cylinder contains about 430,000 BTUs of usable energy (that’s roughly 4.7 gallons), which is why many grills run ~18–20 hours on a full 20 lb tank at moderate heat.
About “full”: the 80% rule
All propane tanks and cylinders are purposely filled to no more than ~80% of liquid capacity to leave room for expansion. If you notice your 500-gallon tank shows ~400 gallons when “full,” that’s by design, and it’s a safety requirement.
A quick “DIY calculator” you can use for anything
- Find the BTU/h rating on the spec label or manual (or the product page).
- Estimate active hours (for cycling equipment like furnaces or water heaters, use your best guess for actual burner-on time).
- Do the math with the formula above.
- Translate to runtime on a given tank by dividing your tank’s available BTUs by the appliance’s BTU/h.
Two fast examples:
- Patio heater (typical “tall mushroom” style ~46,000 BTU/h):
Gallons per hour ≈ 46,000 ÷ 91,452 ≈ 0.50 gal/h. A 20 lb cylinder (~4.7 gal) yields about 9–10 hours on high. (Most retail patio heaters list 40k–48k BTU/h). - BBQ grill (30,000 BTU/h on “medium-high”):
Gallons per hour ≈ 30,000 ÷ 91,452 ≈ 0.33 gal/h. A 20 lb cylinder gives roughly 14–15 hours wide-open—or ~19–20 hours in typical mixed use, matching supplier guidance.
(These are planning estimates. Real results vary with temperature, wind, appliance efficiency, and how often the burner cycles.)
Appliances That Use Propane Tanks (Outdoor & Indoor)
Below is a comprehensive (but not exhaustive) list for homeowners. We note typical BTU ranges you’ll see on product labels, which you can plug into the formula.
Outdoor living & seasonal use
BBQ grills
- Typical label: ~20,000–40,000 BTU/h (3–4 burners).
- Tank: usually 20 lb cylinder.
- Rule-of-thumb runtime on a 20 lb cylinder: ~10–20 total cooking hours depending on heat level. Ferrellgas
Tall patio heaters (freestanding “mushroom” or pyramid)
- Typical label: ~40,000–48,000 BTU/h.
- Tank: 20 lb cylinder.
- Runtime: ~9–10 hours on high per 20 lb tank.
Tabletop patio heaters
- Typical label: ~10,000–12,000 BTU/h.
- Tank: 1 lb disposable canister or hose to 20 lb cylinder.
- Runtime: varies widely; use the formula.
Fire tables & fire pits (propane)
- Typical label: ~30,000–60,000 BTU/h (premium designs can be higher).
- Tank: usually 20 lb cylinder concealed in the base or connected remotely.
- Runtime: often 7–15 hours per 20 lb cylinder, depending on flame height.
Outdoor kitchens (griddles, side burners, pizza ovens)
- Typical label: 12,000–30,000 BTU/h per burner; pizza ovens can be higher.
- Tank: 20 lb cylinder or plumbed to a bulk tank.
RV & camping appliances (portable griddles, heaters, hot-water pods)
- Typical label: wide range; many use 1 lb canisters or a hose to a 20 lb cylinder.
- Tip: cold weather reduces vaporization; use larger cylinders in winter.
Whole-home & indoor comfort (typically on stationary bulk tanks: 120, 250, 325, 500, or 1,000 gallons)
Direct-vent gas fireplaces & stoves
- Typical label: ~20,000–40,000 BTU/h (small to medium units; larger units can exceed 50,000).
- Use: targeted room heating and ambience.
Furnaces & boilers (propane)
- Typical label: ~60,000–120,000+ BTU/h for many propane furnaces and boilers in Nova Scotia homes (larger or older homes may use more).
- Note: runtime depends on thermostat setting, insulation, and weather.
Garage/unit heaters (forced-air or infrared)
- Typical label: ~30,000–80,000+ BTU/h, depending on garage size and insulation.
Water heaters
- Tank-style: commonly ~34,000–50,000 BTU/h.
- Tankless: typically 120,000–200,000+ BTU/h (high-flow units go higher).
- Tankless water heater models are popular for continuous hot water; you can estimate daily gallons using burner size × active minutes per day × efficiency.
Clothes dryers (gas)
- Typical label: ~18,000–22,000 BTU/h.
- Advantage: faster dry times and lower peak electrical demand (especially helpful in winter).
Ranges, ovens & cooktops
- Typical burners: ~7,000–10,000 BTU/h each; ovens often ~16,000–20,000 BTU/h. (Kitchen products are a common PERC category.)
Pool & spa heaters (propane)
- Typical label: 100,000–400,000 BTU/h (400k is a common residential max in Canada/U.S.).
- Pools and hot tubs are high-draw appliances; use the formula to forecast fuel needs before opening weekend.
Standby generators (propane)
- Fuel draw depends on load. For example, a Generac 10 kW unit uses about ~0.97 gal/hr at 50% load; larger 20 kW models commonly span ~1.6–2.5 gal/hr depending on load and model. Always check the spec chart for your exact unit.
Off-grid extras (less common in suburbs)
- Propane refrigerators, space heaters, flame lighting, and torches exist, especially for cabins and farms
How to Pick the Right Tank Size for Each Use
Portable cylinders (DOT):
- 20 lb (most BBQs, patio heaters, many fire tables): ~4.7 gal (~430k BTU).
- 30 lb (RV, higher-draw patio gear): ~7 gal.
- 40 lb: ~9.4 gal.
- 100 lb (high-use appliances, small cabins, temporary heat): ~23–25 gal.
Stationary bulk tanks (ASME):
- 120 gal (small homes, cottages, single big appliance).
- 250/325 gal (multiple appliances, modest home).
- 500 gal (whole-home heating and hot water).
- 1,000 gal (larger homes, whole-home + pool heat, longer refill intervals).
Remember the 80% fill rule: a “full” 500-gallon tank safely holds about 400 gallons of liquid propane. Upsizing a tank can improve cold-weather performance (more surface area for vaporization) and reduce delivery trips, which is useful if you run multiple high-demand appliances.
How to Budget Without Chasing Volatile Prices
Propane pricing varies by season, region, and plan type (will-call vs. scheduled, prebuy, budget plans). Instead of embedding a fast-stale dollar figure, use this method so your estimate stays accurate:
- Estimate gallons with the formula above for each appliance.
- Add a buffer for cold snaps (10–20%).
- Multiply by your supplier’s current price per litre or per gallon (ask for both with taxes/fees included).
- If you’re on whole-home propane, review last year’s seasonal usage and weather. Heating degree days (HDD) drive furnace runtime; your supplier can share last season’s deliveries to refine your forecast.
Tip: If you refill cylinders, track runtime in a note on your phone. For bulk tanks, a wireless tank monitor plus app alerts can help you refill on schedule and avoid emergency fees.
Proven Ways to Use Less Propane (Without Feeling It)
1. Dial in appliance efficiency
- Furnace/boiler: Service annually, replace dirty filters, seal leaky ducts, and consider a high-efficiency upgrade when the time comes.
- Water heating: Insulate hot-water lines where code allows, fix dripping taps, and choose low-flow showerheads that don’t feel “low flow.”
- Cooking/drying: Use residual oven heat; don’t overdry laundry.
2. Use heat where you use space
- For outdoor living, lower flame height on fire tables and heaters after warm-up. Wind fences and overhead cover (respecting clearance to combustibles) reduce heat loss.
3. Cut building heat loss
- Weather-strip doors, improve attic and rim-joist insulation, and seal around penetrations. Every BTU you don’t lose is one you don’t buy.
4. Operate smart in winter
- Keep the tank and regulator clear of snow and ice (consider investing in a heater blanket).
- Maintain adequate tank level (above ~30% in extreme cold) to support vaporization for high-demand appliances.
- If you routinely run several big loads at once (furnace + tankless + fireplace + dryer), consider tank upsizing or a second stage regulator review with a pro.
Safety Essentials (Read Once; Remember Always)
- Hire a professional to install and service equipment according to the Canadian CSA B149.1 Natural Gas & Propane Installation Code (and local rules). Don’t DIY gas piping.
- Respect the 80% fill rule and never try to “top off” a tank or cylinder.
- Store cylinders outdoors, upright and away from ignition sources; transport them upright and secured.
- Use CO and combustible-gas detectors where appropriate; test monthly.
- Leak checks: if you ever smell gas, leave the area and call your supplier—don’t try to relight anything.
Quick Reference Guide for Typical BTU Ranges You’ll See on Labels
(These are typical spec-sheet values, not hard rules. Always use your model’s actual rating for calculations.)
- BBQ grill: 20,000–40,000 BTU/h (3–4 burners).
- Tall patio heater: ~40,000–48,000 BTU/h.
- Fire table: ~30,000–60,000 BTU/h (some designs higher).
- Gas fireplace (direct-vent): ~20,000–40,000 BTU/h typical.
- Tank water heater (propane): ~34,000–50,000 BTU/h; tankless 120,000–200,000+ BTU/h.
- Furnace/boiler (residential): ~60,000–120,000+ BTU/h common.
- Pool heater (propane): ~100,000–400,000 BTU/h typical. =
- Standby generator (propane): see model chart; ~0.97 gal/hr at 50% load for a 10 kW example; 20 kW units often ~1.6–2.5 gal/hr depending on load.
Summary: Bringing it All Together
- List your appliances and note each BTU/h rating.
- Estimate runtime per week (be honest about winter).
- Apply the formula to forecast gallons (or litres).
- Pick tank size for your lifestyle (cylinders vs. bulk).
- Set up deliveries (or add a tank monitor) so you’re never caught empty.
- Review after the season: did you over- or under-estimate? Adjust.
Trust Our Pros for Propane in Nova Scotia
At Ultimate Home Comfort, we can help with the whole journey: selecting and installing propane appliances, choosing the right tank size (or cylinder setup) for your mix of BBQs, patio heaters, fire features, fireplace, water heating and more. Plus, we offer dependable refills and seasonal checkups. If you want, send us your appliance list and we’ll run the numbers with you and recommend a delivery plan that fits your home and budget.
Contact our team today to get started!