April 19, 2025

How Long Does a Gas Bottle Last for a Fire Table?

Fire tables: where cosy vibes meet gas bills. Wondering how long a gas bottle lasts? Short answer: 3 to 50 hours, depending on size, flame height, and weather. Want to stretch your bottle, avoid mid-s’more shutdowns, and save cash? Stick around—your garden glow-up depends on it.

Factors Affecting Burn Time

When it comes to gas bottles and fire tables, there’s no one-size-fits-all answer. Burn time depends on several key factors—from your table’s heat output to how often you fire it up for those weekend garden hangouts. Let’s dive into what really affects how long your gas will last.

Fire Table BTU Rating

Higher BTU Means Faster Gas Consumption

Think of BTUs (British Thermal Units) like your fire table’s hunger level. The higher the BTU, the more fuel it gulps down. A table with 50,000 BTUs will burn through a bottle far quicker than one with 30,000.

It’s great if you want serious heat—but it’s not so great if you’re hoping to make your gas bottle last the month.

Understanding BTU and Heat Output

In simple terms, one BTU is the amount of energy needed to heat a pound of water by one degree Fahrenheit. Most fire tables are rated between 30,000 and 60,000 BTUs per hour.

So if you’ve got a 13kg gas bottle filled with propane, it contains roughly 598,000 BTUs of energy. Divide that by your fire table’s BTU rating, and you’ll get a good idea of how long it’ll last.

Gas Bottle Size

Larger Bottles Provide Longer Burn Times

This one’s a no-brainer—the bigger the bottle, the longer it lasts. A 5kg propane bottle might get you through a dinner party. A 47kg bottle? That’s a whole summer’s worth of garden sessions.

If you’re using your fire table regularly, it might be worth upgrading to a larger size to save on constant refills.

Common Propane Bottle Sizes

Here are the most common gas bottle sizes used in the UK for outdoor fire tables:

5kg – Perfect for portable tables and short gatherings (approx. 3–5 hours of burn time)
13kg – Ideal for regular use (approx. 8–12 hours)
47kg – Best for larger setups or commercial use (approx. 40–50 hours)

Choosing the right size isn’t just about how long it lasts—it’s also about how much hassle you want to avoid.

Flame Setting and Usage

High vs. Low Flame Settings

If you’re blasting your fire table on full power, expect the gas to vanish faster than snacks at a BBQ. Turning it down just a notch can dramatically stretch out your burn time.

Think of it like driving: full throttle burns through fuel, but cruising gives you better mileage. A lower flame still keeps things warm, just more economically.

Frequency and Duration of Use

Naturally, the more often you use your fire table, the more gas you’ll go through. If you're lighting it up every evening, a 13kg bottle might only last a week or two.

But if it’s only for special occasions, you might get a month or more out of it. Keep a rough log of your usage—it can really help with planning refills.

Calculating Burn Time

So, how do you actually work out how long a gas bottle should last? The good news is, it’s not rocket science—just a bit of simple maths and a dash of common sense.

Formula for Estimating Burn Time

Relating BTU, Bottle Size, and Usage

Here’s the basic formula:

Burn Time (hours) = Bottle BTUs ÷ Fire Table BTUs per Hour

Propane provides roughly 46,000 BTUs per kilogram. So:

5kg bottle = 230,000 BTUs
13kg bottle = 598,000 BTUs
47kg bottle = 2,162,000 BTUs

Divide by your fire table’s BTU rating and you’ve got your estimated run time.

Example Calculations

Let’s say your fire table runs at 50,000 BTUs/hour:

5kg bottle: 230,000 ÷ 50,000 = 4.6 hours
13kg bottle: 598,000 ÷ 50,000 = 11.96 hours
47kg bottle: 2,162,000 ÷ 50,000 = 43.24 hours

These are continuous-use estimates. If you only run your table for an hour or two a few times a week, you’ll get plenty of evenings out of even a small bottle.

Real-World Examples

Burn Time for Different Bottle Sizes and BTU Ratings

Here’s a quick reference chart to help you plan:

Gas Bottle Size	Fire Table BTU Rating	Approx. Burn Time
5kg	40,000 BTU/hour	~5.75 hours
5kg	50,000 BTU/hour	~4.6 hours
13kg	40,000 BTU/hour	~15 hours
13kg	50,000 BTU/hour	~12 hours
47kg	50,000 BTU/hour	~43 hours

Keep in mind, real-world results may vary depending on wind, ambient temperature, and how high you set the flame.

Tips for Extending Burn Time

Want to keep your fire table running longer between refills? Here’s how to get the most out of every bottle.

Using Lower Flame Settings

Balancing Heat Output and Gas Consumption

We all love a roaring fire—but sometimes, less really is more. A medium flame often provides more than enough warmth for a chill evening.

Try dialling it down a notch and you’ll be surprised at how much longer your gas lasts, without sacrificing comfort.

Optimising Fire Table Efficiency

Wind Protection and Proper Maintenance

Wind can wreak havoc on your flame, making the table work harder to stay lit. Try setting up a windbreak or positioning your fire table in a sheltered corner of your garden.

Also, check your connections regularly, clean your burners, and look out for leaks. A bit of maintenance goes a long way in keeping things efficient (and safe).

Conclusion

So, how long does a gas bottle last for a fire table? The answer ranges from 3 to 50 hours, depending on factors like bottle size, BTU rating, flame height, and how often you use it.

But the secret to stretching out your gas isn’t just about bigger bottles—it’s about smart usage. Lower your flame, protect from wind, and give your fire table a little TLC now and then. Whether it’s weekend wine nights, midweek marshmallow sessions, or full-on garden parties, you’ll be ready for anything.

Your fire table is more than just a heater—it’s the heart of your outdoor space. And with a bit of planning, it can stay glowing all season long.