The question of whether to use a coal forge or a propane forge is one that most beginning Canadian smiths encounter early and sometimes return to later as their work and shop situation change. Both fuels are viable for serious blacksmithing. The differences lie in how they behave, what infrastructure they require, and how practical each is in a given part of the country.
How Each Forge Heats the Metal
A coal forge creates a fire in a firepot — a cast-iron or fabricated steel bowl — through which air is forced by a hand-crank blower or an electric blower motor. The blacksmith nests the workpiece in the fire, controlling depth of heat by adjusting air flow and the position of the stock relative to the hottest zone of the fire. A well-managed coal fire reaches temperatures between 1,200°C and 1,450°C in its core — sufficient to bring mild steel to a bright yellow or white heat for forge welding.
A propane forge burns a mixture of propane and air through one or more venturi or blown burners, heating a refractory-lined chamber. The workpiece is placed inside the chamber and heated by radiant energy and the surrounding atmosphere. Propane forges with a single burner typically sustain temperatures between 1,100°C and 1,250°C in steady state, which is sufficient for most forging work but can be tight for forge welding. Two-burner and blown-burner propane forges reach higher temperatures and handle larger stock.
Forge Welding Considerations
Forge welding — joining two pieces of iron or steel by heating them to welding temperature (roughly 1,300–1,400°C for mild steel) and striking them together — is easier to achieve in a coal forge than in most propane setups. Coal fire allows the smith to produce a reducing (oxygen-depleted) atmosphere around the stock, which prevents the heavy oxidation that interferes with welding. Propane forges can be tuned to run rich (low oxygen), but the adjustment is less intuitive and the margin is tighter.
For smiths whose work does not include forge welding, this distinction carries little practical weight. For those making chains, hooks with welded eyes, or traditional hardware where welded joints are part of the construction, a coal forge is easier to work with.
Sourcing Fuel in Canada
Blacksmithing coal is a specific product: bituminous smithing coal, also called metallurgical coal or forge coal. It should coke readily (form a hard, porous mass that burns with intense heat) and have low sulfur content. Coal sold for residential heating is often not suitable — it may be lignite, which does not coke well, or it may have sulfur levels that contaminate the surface of the steel.
In Canada, smithing coal is most accessible in:
- Alberta and British Columbia: mining heritage means coal is available through farm supply and feed stores in some rural areas, and through specialty suppliers.
- Ontario and Quebec: supply is patchier. Some farrier supply companies carry forge coal. ABANA-Canada chapters often maintain contact lists for coal sources by region.
- Atlantic provinces: historical coal-mining areas around Cape Breton and Pictou County in Nova Scotia occasionally have local access, but regular supply can be inconsistent.
Propane is universally available across Canada through any standard supplier. Pricing varies by region, and consumption rates in a forge — typically 1–2 lb of propane per hour for a single-burner unit at steady state — add up over a full working day. A 20 lb cylinder (the standard barbecue tank) provides approximately 10–20 hours of forging depending on the burner and the ambient temperature.
Ventilation Requirements
A coal forge requires a hood and chimney to exhaust smoke, carbon monoxide, and combustion byproducts. The chimney must draw well, which means adequate height above the roofline and a well-fitting smoke hood positioned directly over the fire. A poorly ventilated coal shop fills with smoke quickly — a genuine health hazard. In Canada, building a proper chimney flue involves meeting local building codes and, in some municipalities, obtaining a permit.
A propane forge requires ventilation for combustion gases and carbon monoxide, but does not produce smoke. A simple exhaust fan drawing air from near floor level (where propane vapor settles) and a ceiling vent for CO are usually sufficient. Many smiths operate propane forges in garages with a door open and a ceiling fan running. This is a considerably simpler setup than a coal forge flue.
Municipal and Provincial Regulations
Regulations affecting home forges vary by province and municipality. In general:
- Open flame appliances in residential structures are subject to local fire codes. A forge in an attached garage may require a fire separation wall between the forge area and the living space.
- Propane storage is regulated by provincial fire codes. Most jurisdictions permit storage of standard exchange cylinders (up to 20 lb) in an outdoor, ventilated enclosure.
- Solid-fuel appliances including coal forges may require a WETT (Wood Energy Technology Transfer) inspection in some provinces, or an equivalent certification depending on jurisdiction.
- Commercial operation out of a residential property — selling forged goods made on-site — triggers different zoning considerations than hobby use.
The relevant provincial codes to reference are the National Building Code of Canada (as adopted by each province), the National Fire Code of Canada, and provincial Propane Storage and Handling regulations. Municipal bylaws may impose additional restrictions, particularly in urban and suburban areas.
Which Setup to Choose
For a smith setting up in a rural area with access to smithing coal and an existing outbuilding that can be fitted with a chimney, a coal forge is a practical choice. The fuel is comparatively inexpensive by the bag, the fire is easy to control once the technique is established, and the forge welding capability is a genuine advantage.
For a smith in a suburban or urban setting — which describes much of the Canadian smith population today — a propane forge is easier to install, easier to comply with regulations, and easier to manage in terms of fuel storage. The limitation on forge welding temperatures matters for some work but not most.
Many established smiths run both: a coal forge for welding and long sessions on larger work, and a propane forge for quick heat on short pieces or when working in a situation where the coal setup is impractical.
