Heater Buying Guide: How to Choose the Right Heater
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Choosing the right heater isn't simply about finding the highest BTU rating.
The best heater for your application depends on what you're heating, the size and construction of the space, insulation, outdoor temperature, ventilation, available fuel or power, and how you want the heat delivered.
Whether you're heating a garage, workshop, construction site, temporary structure, outdoor area or large industrial space, this guide will help you understand the most important factors to consider before you buy.
Safety First! Heater Safety Features and Certifications in Canada
Safety should be the first thing you consider when choosing a heater—not an afterthought.
Never assume that a heater is safe to use indoors simply because it is sold as a "space heater" or because it is marketed as indoor-safe in another country. Canadian safety requirements and recommendations can differ from those in the United States.
For fuel-burning heaters, including propane and natural gas models, proper ventilation and the heater's intended application are critical. Fuel combustion can produce carbon monoxide, and using outdoor-rated equipment indoors or in poorly ventilated spaces can allow dangerous concentrations of CO to build up.
If you plan to use a heater indoors, verify that the exact model is specifically designed and certified for indoor use in Canada and follow the manufacturer's installation and ventilation requirements. An outdoor propane patio heater, for example, should not be brought into a garage, workshop, enclosed porch or other indoor space simply because there is a door or window that can be opened.
When shopping for a heater, look for:
- Appropriate Canadian certification for the product and intended application
- Automatic shut-off if the heater tips over
- Overheat protection
- Safety grills or guards where applicable
- Clear manufacturer's instructions for indoor or outdoor use
- Appropriate ventilation and clearance requirements
For enclosed spaces, electric heaters are often the simplest option because they do not produce combustion gases or carbon monoxide.
Canadian safety reminder: If a propane or other fuel-burning heater is intended for outdoor use, keep it outdoors. Do not rely on a US product description or online advice to determine whether a heater is suitable for indoor use in Canada.
What Kind of Heater Do You Need?
Before comparing individual heaters, start with these five questions:
1. What are you heating?
A garage, workshop, construction site, outdoor area, temporary structure or large commercial space?
2. How large is the space?
Consider not only square footage, but also ceiling height and the overall volume of the space.
3. What's your fuel or power source?
Propane, natural gas, kerosene/diesel or electricity?
4. How do you want the heat delivered?
Radiant, forced air, convection or indirect-fired?
5. What conditions will the heater operate in?
Consider outdoor temperature, insulation, drafts, open doors and ventilation.
Once you understand these factors, you can use BTU output and the heater's specifications to narrow down your choices.
1. What Are You Trying to Heat?
The right heater for a small workshop may be completely different from the right heater for a construction site.
Start with the application.
Garage or Workshop
For garages and workshops, consider:
- The size and ceiling height of the space
- How well the building is insulated
- How often doors are opened
- Whether you need temporary or permanent heat
- Whether natural gas, propane or electricity is available
- Whether you need to heat the entire space or primarily your work area
A small, insulated workshop has very different heating requirements from a large, drafty garage with an overhead door that is frequently opened.
Construction Site or Jobsite
Construction heating often involves large, drafty or partially enclosed spaces where doors may remain open and insulation may be limited.
Portable forced-air heaters are commonly used for temporary construction heating, but the appropriate heater depends on the application, fuel source, ventilation, electrical supply and the manufacturer's requirements.
Outdoor and Personal Heating
If you're trying to keep yourself or a small group warm outdoors, a compact radiant or portable heater may make more sense than a large forced-air heater.
For these applications, portability, fuel capacity, heat direction and runtime can be just as important as BTU output.
Large or Temporary Spaces
Large construction areas, industrial spaces, event structures and other temporary applications can require substantially more heating capacity.
This is where higher-output forced-air and indirect-fired heaters can become useful.
2. How Much Heat Do You Need?
Understanding BTUs
When shopping for heaters, you'll quickly come across the term BTU.
BTU stands for British Thermal Unit. Heater specifications commonly use BTU/hr to describe the amount of heat energy a heater can produce over an hour.
BTU output is an important specification when comparing heaters—but BTU alone does not determine whether a heater is suitable for your space.
As a general shopping reference, heaters can be grouped roughly into these ranges:
| BTU Output | Typical Applications |
|---|---|
| Under 20,000 BTU | Personal and portable heating |
| 20,000–50,000 BTU | Smaller garages, workshops and portable applications |
| 50,000–100,000 BTU | Larger garages, workshops and jobsites |
| 100,000–200,000 BTU | Large construction and commercial applications |
| 200,000+ BTU | Large-volume industrial and temporary heating |
These ranges are intended as a starting point for comparing heaters, not as a universal sizing formula.
Two spaces with the same square footage can have very different heating requirements.
3. BTU Is Only Part of the Equation
Before choosing a heater based on BTU output, consider the conditions in which it will operate.
Space Size
Square footage is important, but don't forget ceiling height.
A 1,000-square-foot room with an 8-foot ceiling contains significantly less air than a 1,000-square-foot shop with a 20-foot ceiling.
Insulation
An insulated building generally holds heat much better than an uninsulated garage, shed or temporary structure.
Outdoor Temperature
A heater that works well during a mild fall day may not provide enough capacity during the coldest part of a Canadian winter.
Air Leakage
Drafts, open doors, windows and other sources of air exchange can significantly increase heat loss.
Desired Temperature
Think about the temperature you're actually trying to achieve.
There's a difference between wanting to take the chill off a workspace and needing to maintain a specific temperature throughout an entire building.
How the Space Is Used
A garage, workshop, tent, construction site and warehouse can all have very different heating requirements.
The right heater is determined by the entire application—not just the number on the BTU rating.
4. Choose Your Fuel or Power Source
The fuel or power available at your location can narrow down your heater choices considerably.
Before choosing a heater, consider:
- What fuel or power is available?
- How easy is it to replenish?
- What does the heater require to operate?
- How portable does the heater need to be?
- How long will it need to run?
- What electrical supply is available?
Propane Heaters
Propane heaters are popular for portable, construction, garage and outdoor applications.
Advantages can include:
- Portable fuel supply
- High heat output
- Many portable heater options
- No natural-gas connection required
However, propane heaters have specific ventilation, clearance, fuel-storage and operating requirements. Always follow the manufacturer's instructions for the specific model.
Natural Gas Heaters
Natural gas can be convenient for permanent or semi-permanent heating where a suitable gas supply is available.
Natural-gas heaters are commonly used for garages, workshops and building-heating applications.
Because they typically connect to a fixed gas supply, they are generally less portable than cylinder-powered propane heaters.
Installation requirements vary by heater and location, so follow the manufacturer's instructions and applicable local requirements.
Kerosene and Diesel Heaters
Fuel-fired forced-air and indirect-fired heaters can provide high heat output for construction, industrial and temporary applications.
These heaters can be useful where substantial portable heating capacity is required.
Fuel compatibility varies by model, so always use only the fuels specified by the manufacturer.
Electric Heaters
Electric heaters can be convenient where adequate electrical power is available.
They don't require combustion fuel, but their output is limited by the electrical supply available to the heater.
Before buying an electric heater, check:
- Voltage
- Amperage
- Plug type
- Circuit requirements
- Generator requirements, if applicable
5. Understand the Different Types of Heat
Different heaters deliver heat in different ways.
Understanding these differences can make choosing the right heater much easier.
Radiant Heaters
Radiant heaters warm people and objects directly rather than relying primarily on heating and circulating the surrounding air.
They're particularly useful when you want focused heat on people or specific areas.
Think:
"I want to warm the people or objects in front of the heater."
rather than:
"I need to heat all of the air in the building."
Radiant heating is commonly found in patio, camping, hunting and other personal or localized heating applications.
Forced-Air Heaters
Forced-air heaters use a fan or blower to move heated air.
They're commonly used for temporary heating of construction sites, garages, workshops and other spaces where moving warm air through the area is desirable.
Think:
"I want to move a large volume of heated air through the space."
Forced-air heaters can heat a space quickly, but heated air can also be lost quickly when cold outside air enters the space.
Convection Heaters
Convection heaters warm the surrounding air, which then circulates through the space.
They can be useful when you want more gradual, ambient heating rather than highly directional heat.
Indirect-Fired Heaters
Indirect-fired heaters use a heat exchanger to separate the combustion process from the heated air.
The heater transfers heat to the air while combustion exhaust is directed through a separate exhaust path.
This allows indirect-fired heaters to provide heated air with combustion exhaust kept separate from the heated air stream.
They are commonly used for large construction, industrial and temporary heating applications where this configuration is appropriate.
6. Direct-Fired vs. Indirect-Fired Heaters
If you're shopping for a larger fuel-fired heater, understanding the difference between direct-fired and indirect-fired equipment is important.
Direct-Fired
With a direct-fired heater, combustion takes place directly in the airstream being heated.
This can make direct-fired heaters effective for many temporary heating applications, but combustion products enter the heated space.
The heater therefore has specific ventilation and application requirements.
Indirect-Fired
An indirect-fired heater uses a heat exchanger to keep combustion exhaust separate from the heated air.
The heated air can then be ducted to the space while the combustion exhaust is handled separately.
In simple terms:
Direct-fired
Fuel → Combustion → Heated air → Space
Indirect-fired
Fuel → Combustion → Heat exchanger → Heated air → Space
↓
Separate exhaust
Neither type is automatically "better."
The right choice depends on the application, occupancy, ventilation, desired setup and the manufacturer's specifications.
7. Radiant Heat or Forced Air?
If you're deciding between radiant and forced-air heating, start by asking what you're actually trying to warm.
Radiant heat may make sense when:
- You're primarily trying to warm people
- You want localized heat
- Heating the entire volume of air isn't necessary
- You want focused, directional warmth
Forced air may make sense when:
- You want to move heated air through a space
- You're heating a larger area
- You need portable temporary heat
- You're working in a suitable construction or jobsite application
Neither is universally better.
The right choice depends on your application.
8. Portable or Permanent?
Another important question is:
Will this heater move, or will it live here?
Portable Heaters
Portable heaters make sense when you need to move heat between locations or only need temporary heating.
Consider:
- Weight
- Handles or wheels
- Fuel capacity
- Power requirements
- Setup time
- Storage
Permanent or Mounted Heaters
If you're heating the same garage, workshop or building regularly, a mounted or permanent heating solution may make more sense.
These systems can require more planning and installation, so check the manufacturer's specifications and applicable local requirements before purchasing or installing one.
9. Consider Ventilation and Safety
Fuel-burning heaters require particular attention to ventilation, clearances, fuel handling and the intended application.
The requirements vary significantly between heater types and models.
Before operating any heater:
- Read the owner's manual
- Confirm that the heater is approved for your intended application
- Follow required clearances
- Follow ventilation requirements
- Use only the specified fuel
- Follow electrical requirements
- Keep combustible materials away from the heater
- Never modify safety systems
- Never operate equipment with required parts missing
- Follow applicable local codes and regulations
Never assume that because a heater produces heat, it is appropriate for an enclosed space.
A fuel-burning heater's suitability for an indoor or enclosed application depends on the specific model, its certification, ventilation requirements and intended use.
Always follow the manufacturer's instructions for the heater you are using.
10. Consider Your Electrical Requirements
Some fuel-burning heaters also require electricity to operate fans, controls or ignition systems.
Don't assume that a fuel-powered heater is completely independent of electricity.
Before buying, check:
- Voltage
- Amperage
- Plug type
- Required circuit
- Extension-cord requirements
- Generator compatibility, if applicable
This becomes particularly important for construction sites and temporary installations.
11. Think About Ducting
For certain larger heaters, ducting can be an important part of the setup.
Indirect-fired heaters are often designed to deliver heated air through ducting, allowing heated air to be directed to specific areas.
When comparing models, look at:
- Maximum duct length
- Duct diameter
- Number of outlets
- Airflow/CFM
- Static pressure requirements
- Available accessories
Don't choose a heater based solely on BTUs if your application depends on moving heated air through ducting.
12. Consider the Canadian Climate
If you're buying a heater in Canada, winter conditions matter.
Consider:
- The lowest outdoor temperatures you'll encounter
- Wind exposure
- Building insulation
- How often doors are opened
- Whether the space is occupied
- Whether the heater needs to operate continuously or intermittently
A heater that performs adequately during a mild fall day may not provide enough capacity during extreme cold.
For demanding applications, consider the conditions you'll actually encounter rather than sizing around an average day.
13. Don't Forget Your Fuel Supply
The heater isn't the entire heating system.
Before buying, make sure you have a practical way to supply it with fuel.
Propane
Consider:
- Cylinder size
- Number of cylinders
- Regulator requirements
- Hose requirements
- Refilling or exchanging cylinders
- Expected runtime
Kerosene / Diesel
Consider:
- Fuel storage
- Fuel quality
- Refueling frequency
- Appropriate fuel type for the model
Natural Gas
Consider:
- Existing gas supply
- Required gas pressure
- Connection requirements
- Installation requirements
Electricity
Consider:
- Available voltage
- Circuit capacity
- Extension-cord requirements
- Generator capacity, if applicable
The best heater on paper isn't useful if your site can't support it.
14. Choosing a Heater for Your Garage
There's no single "best garage heater" because garages vary enormously.
Before choosing a garage heater, consider:
How large is the garage?
How high is the ceiling?
Is it insulated?
How often does the garage door open?
Do you need to heat the entire garage or just your workspace?
Do you have natural gas, propane or electricity available?
Do you want a portable heater or a permanent heating solution?
For a well-insulated workshop that you heat regularly, a different solution may make sense than for a large, drafty garage that is only occupied occasionally.
15. Choosing a Construction Heater
Construction sites often have challenging heating conditions:
- Large open areas
- Poor insulation
- Open doors
- Temporary structures
- Changing work areas
- Cold outdoor temperatures
Portable forced-air heaters are commonly used for temporary construction heating, but the correct choice depends on the fuel source, required heat output, ventilation, electrical supply and the specific site conditions.
For larger applications where ducted heated air is required, indirect-fired heaters may be worth considering.
16. Choosing a Portable Outdoor Heater
If you're heating yourself rather than an entire building, a smaller portable radiant heater may make more sense than a large forced-air unit.
Think about:
- Portability
- Fuel capacity
- Electrical requirements
- Heat direction
- Runtime
- Intended location
- Weather conditions
A heater doesn't need to heat an entire building if you're only trying to keep one person or a small area warm.
17. Don't Automatically Buy the Biggest Heater
More BTUs aren't automatically better.
A larger heater may cost more to purchase and operate, while its physical size, fuel requirements and airflow may make it less convenient for your application.
Instead of asking:
"What's the biggest heater I can afford?"
ask:
"What heater is appropriate for the way I actually intend to use it?"
That's a much better starting point.
18. Think About Ownership—not Just the Purchase
A heater is a piece of equipment.
And good equipment is worth maintaining.
Before you buy, consider:
- Are replacement parts available?
- Can common wear items be replaced?
- Is a parts schematic available?
- Are manuals available?
- Are accessories available?
- Can the heater be maintained over time?
At LionCove, we believe buying equipment should be about more than the initial purchase.
Buy thoughtfully. Maintain what you own. Repair instead of replace.
A heater shouldn't become disposable because one component wears out.
LionCove carries replacement parts and accessories for many of the heaters we sell, helping you maintain, repair and keep your equipment working for years to come.
19. Heater Buying Checklist
Before you buy, ask yourself these questions.
Application
☐ What am I heating?
☐ Is the space indoor, outdoor, temporary or permanent?
Space
☐ How large is the space?
☐ How high are the ceilings?
☐ How well insulated is it?
☐ How much air leakage is there?
Conditions
☐ What outdoor temperatures will I encounter?
☐ What temperature am I trying to achieve?
☐ Will doors or openings remain open?
Heat
☐ Do I need radiant or forced-air heat?
☐ Do I need direct-fired or indirect-fired heat?
☐ What BTU range should I be looking at?
Fuel & Power
☐ What fuel is available?
☐ Can I supply enough fuel?
☐ What electrical supply does the heater require?
Setup
☐ Is the heater portable or permanent?
☐ Do I need ducting?
☐ Are there clearance or ventilation requirements?
Ownership
☐ Are replacement parts available?
☐ Are accessories available?
☐ Can I maintain and repair the heater over time?
Still Not Sure Which Heater You Need?
That's okay.
The right heater isn't determined by BTU alone. Start with your application, space, fuel source and heat type, then narrow your choices based on BTU output and the manufacturer's specifications.
If you're comparing several heaters and aren't sure which configuration is appropriate, contact LionCove and we'll help you work through the specifications.
Ready to Shop LionCove's Heaters & Heating Equipment?
From compact portable heaters to large-capacity construction and indirect-fired equipment, LionCove offers heating equipment for Canadian garages, workshops, jobsites, outdoor spaces and industrial applications.
A Note on Heater Safety
This guide is intended to help you understand the factors involved in choosing a heater. It is not a substitute for the owner's manual, manufacturer's instructions, professional installation advice, or applicable local codes and regulations.
Look for appropriate Canadian certification, automatic shut-off and overheat protection. For enclosed spaces, only use a fuel-burning heater that is specifically designed and approved for indoor use in Canada. Never use an outdoor-rated propane heater indoors.
Heater requirements vary by model and application. Always confirm that a specific heater is approved for your intended use and follow all manufacturer instructions for fuel, ventilation, clearances, electrical supply and operation.
When in doubt, consult the documentation for the specific heater rather than relying on general information about a heater type.