Wood Pellets

Wood pellets are small cylinders of compressed, dried sawdust and wood shavings, typically 6-8 mm in diameter, held together by the wood’s natural lignin — no glue, no chemicals, no binder. That’s the whole story on what they are. The buying decision comes down to one thing: grade. Get it wrong, and you’ll fight clinker, excess ash, and a stove that doesn’t run the way it should.

For broader project planning, explore WBC’s building materials resources.

Here’s the rule that matters most. Residential systems require Premium-grade pellets (ENplus A1 or PFI Premium), characterized by ash content ≤ 1.0%, moisture ≤ 8-10%, fines ≤ 0.5%, and high BTU output (≥ 8,000 BTU/lb). Anything below that grade belongs in industrial equipment, not your home appliance. Western Building Center carries 40-pound bags of Purcell pellets and a premium North Idaho pellet, both in the 40# bag size that feeds standard residential hoppers.

For Montana, the case for pellets writes itself in rural country without natural gas service. Pellets are a clean, uniform, and automated fuel source — gas-like convenience from a wood fuel, fed automatically through a hopper instead of hand-loaded like cordwood.

Grades, Specs, and What Burns Hottest

Pellets get sorted by ash content, because ash is what fouls a burn pot and builds clinker. Two certification systems cover the market.

Grade	Standard	Max Ash	Use
Premium (US)	PFI Premium	≤ 1.0%	Residential
Standard (US)	PFI Standard	≤ 2.0%	—
Utility (US)	PFI Utility	≤ 6.0%	Industrial
A1 (EU)	ENplus A1	≤ 0.7%	Residential
A2 (EU)	ENplus A2	≤ 1.2%	—
B (EU)	ENplus B	≤ 2.0%	—

Always check what your appliance actually calls for. Verify your appliance’s specific fuel requirements, as lower-grade fuels (Industrial/Utility) may cause issues in residential units.

Species matters too. Softwood pellets generally offer higher heat output due to resin content, while hardwood may be more available regionally. Either way, the energy numbers favor pellets over cordwood. Wood pellets are compressed cylinders of dried wood waste, typically 6 to 8mm in diameter, with moisture content below 10%. Firewood is split, seasoned timber with moisture typically ranging from 15% to 25% when properly dried. On heat content, A1-grade wood pellets have a calorific value of roughly 4.9 kWh per kilogram. Well-seasoned hardwood firewood typically delivers between 3.5 and 4.2 kWh per kilogram, depending on species.

That moisture gap is where the efficiency comes from. Burning wet or poorly seasoned wood wastes up to 30% of the fuel’s energy as steam rather than heat. Pellets sidestep that problem by design.

Storage Is Non-Negotiable in Montana

This is where most people waste money. Pellets are bone-dry by design, and they don’t tolerate getting wet. Moisture swells them, breaks them down, and turns a good bag into useless mush. Keep pellets dry to prevent swelling and disintegration. Use dedicated silos, lined bunkers, or off-the-floor storage.

In Montana’s snow, freeze-thaw, and damp ground conditions, off-the-floor is not a suggestion. Pallets, racks, sealed bins — whatever keeps them up and dry through the wet season. The upside is they pack down small. Pellets store compactly in bags or a silo; firewood requires an outdoor log store.

If you’re storing bulk, ventilate it. For bulk storage, ensure ventilation and CO monitoring, as fresh pellets can off-gas.

Pellets vs. Firewood — Which Fits Your Setup

The choice isn’t about which fuel is “better.” It’s about how you heat. Pellets win on automation and efficiency. Firewood wins on simplicity and lower upfront cost.

Efficiency is the clearest split. A modern pellet boiler operates at 85% to 93% efficiency. A high-quality log burner typically runs at 70% to 80% efficiency. Open fires fall off a cliff — an open fire with no insert drops to as low as 25% efficiency.

Where pellets earn their keep is hands-off, whole-home heat. The fuel is standardized, the feed is automated, and combustion is controlled. For heating systems in apartments or newer homes where precise temperature control matters, pellets consistently outperform firewood on efficiency. In Montana, where heating loads run high all winter, that efficiency advantage adds up over a long season.

The trade-offs are real, and worth knowing before you commit. Automated wood pellet burners tend to be costly and require regular maintenance to ensure proper functioning. They also tend to be noisy. And, unlike conventional log burners, they usually cannot be operated without electricity. That last point matters in country where winter storms knock out power. Firewood, by contrast, is loved for its simplicity and ease of use. It isn’t as fussy as briquettes and pellets in terms of required storage conditions. It’s easy to light and intuitive to use.

Worth noting where pellets sit against briquettes. The main difference between briquettes and pellets is their size. Briquettes usually weigh 1-2 kilos, while pellets are bullet-sized — same compressed-residue concept, scaled for an automated feed.

Installation Basics

Don’t freelance the venting. Installation requires adherence to manufacturer specifications and local building codes, specifically regarding venting, clearances to combustibles, and floor protection.

For boiler setups, plan on more than the appliance itself. Most systems need a buffer tank to manage heat output and prevent boiler short-cycling.

On who does the work: While some DIY installations are feasible for simple direct-vent setups, professional installation is recommended for complex venting, multi-story projects, or when mandated by local code.

You’ll want a way to light them, too. Fire starters live alongside pellets for ignition — products like pellet starters, fatwood, and one-match pellet starters handle getting the burn pot going.

Frequently Asked Questions

What grade of wood pellet do I need for a home pellet stove? Premium grade. Residential systems require Premium-grade pellets (ENplus A1 or PFI Premium), characterized by ash content ≤ 1.0%, moisture ≤ 8-10%, fines ≤ 0.5%, and high BTU output (≥ 8,000 BTU/lb). Lower grades are built for industrial equipment and can cause problems in a residential unit.

What size do residential pellets come in? The standard residential package is the 40-pound bag, which is what feeds a home hopper. Western Building Center carries 40# bags in a Purcell pellet and a premium North Idaho pellet.

Are softwood or hardwood pellets better? It depends on what you’re after. Softwood pellets generally offer higher heat output due to resin content, while hardwood may be more available regionally.

How should I store pellets so they don’t go bad? Dry and off the floor. Keep pellets dry to prevent swelling and disintegration. Use dedicated silos, lined bunkers, or off-the-floor storage. In Montana’s wet, freeze-thaw conditions, moisture is the fastest way to ruin a bag.

Are pellets more efficient than firewood? Generally yes, mostly because of moisture. A modern pellet boiler operates at 85% to 93% efficiency. A high-quality log burner typically runs at 70% to 80% efficiency.

Do pellet stoves need electricity? Yes. Unlike conventional log burners, they usually cannot be operated without electricity. That’s a real consideration in areas where winter storms cause outages.

Can I install a pellet appliance myself? Sometimes. While some DIY installations are feasible for simple direct-vent setups, professional installation is recommended for complex venting, multi-story projects, or when mandated by local code.