Heritage Restoration, Inc.

Compressed Wood Fuels

photoMy search for the most efficient, cost-effective, environmentally responsible heating system continues.  I know geothermal heating systems are a great low impact, high yield heating systems, although the buildings they are installed into need to be fairly air tight and well insulated for the system to remain efficient, where few existing New England buildings fit that category.

Many of us cannot afford to retrofit a building with a new heating system.  This year’s record snow, cold, and wind required blasts of heat to stay warm, and keeping up with the heating bill has been hard and the region’s fuel shortages raising prices doesn’t help.

Several years ago I sought to counter my house’s high oil heating bill by installing a wood burning combustion stove.  My house is early 20th century is on its way to being more energy efficient with a new boiler, better insulation, air sealing, and storm windows, but it is still a heat hog.  The wood stove cut the heating bills in half, although there were days the wood stove could barely keep without using the oil heat.  This year’s rain and snow didn’t help; making even covered wood wet and inefficient.  I couldn’t build up enough wood reserves for 2 years, so the seasoning wasn’t long enough.  Also I was running low on wood, and anything I would buy was wetter than usual.  The wet wood made me burn more than I should and made the stove not as hot as it could be.

A friend posted a great idea; using compressed wood fuel(CWF) as an alternative.  CWF had me interested for a few reasons.  First the bricks were dry, very dry.  The second is they use what would normally be waste, so it is renewable.  I know trees are renewable, but trees are not just used for firewood, they are used for many other uses like building products and pallets, which make a lot of sawdust.

Compressed wood pellets have been around since the 1980s.  They are a great source for heat, and can be easily shipped, stored, and used, but only for wood pellets stoves not fireplaces or wood stoves.  That is where the bricks come in.  CWFs burn hotter, cleaner, and last longer than regular firewood.  They are renewable, made from 100% wood, and sustainable “carbon neutral” fuels, where they emit the same amount of CO2 when burned that can be absorbed by forests.  They are made without bark, so they are free of bugs, dirt, mold, and fungus, and they create far less creosote and ash than firewood.
CWFs are made without using any glues or binders, putting wood chips, shavings, and sawdust into a machine that creates a uniform dough-like mass.  The dough is put into a hydraulic press, where the extreme pressure increases the wood’s temperature, naturally binding the product together as it cools.

I got my first order of bricks in a pallet of 66 packages of 15 bricks, weighing over a ton.  The pallet is about the equivalent of a cord and a half, so the price is about the same.  The advantage will be the consistency of the burn and the heat output.  I have a pretty big stove that seemed to never get it hot enough, clearly from the wood’s excessive moisture.  I started conservatively by putting in about 6 bricks.  They caught fire really fast and the heat was hot and consistent for about 3 hours.  While the stove can fit about 60 bricks, I could never imagine filling it up since it will overheat the stove.  The first week was a bit warmer, so I only needed about 20 bricks to last the night.  Always experiment to see what is best for your stove or fireplace. The CWF expands slightly when burned and should not be placed against glass doors or piled against top load doors, or other parts of your stove that are not lined with fire brick or metal plates.  I did mix a bit of wet firewood, which did little except use up what I had left.

So I have to say I may never go back to firewood.  I find little joy in cutting, splitting, moving, stacking and falling, covering, moving again, and cleaning up the mess.  The CWFs do fray a bit, with some dust falling off, but hey, it’s better than wood chunks and dirt.  I may never go back to our forefather’s fuel of choice.

Follow up:

I received a number of inquiries about Compressed Wood Fuels(CWF).  CWF, compressed wood bricks or logs, or bio products are generic names for the same product.  There are a number of manufacturers throughout the US using national and local big box, hardware, general merchandise, and wood stove and fireplace supply stores.  Most sell in smaller packages of 3 to 8 bricks.  Lumber yards and direct regional manufacturers can deliver in bulk saving money, but the product must be stored in a dry location.

According to various studies, wood stoves burn more efficiently with less off gassing with dry, seasoned wood.  Compressed wood fuels reduce emissions from lower, more predictable moisture content.  Newer stoves are rated to release less pollution, and according to the California EPA Air Resources Board, “because of incomplete combustion, old wood stoves can produce up to 50 grams of particulate per hour. EPA Certified fireplace inserts and EPA Certified wood stoves are considerably more efficient, producing only 6 grams per hour. EPA Certified devices create the right conditions for complete combustion; the right amount of air, high temperature, and time to allow the gases to fully burn.”

Fireplaces allow more heat and pollutants to escape, burning far more fuel than wood stove inserts. Wood is considered a renewable energy source that is “carbon neutral,” meaning that it won’t add more carbon dioxide to the atmosphere when burned than left in the forest to rot.   Compressed wood pellets, bricks and logs further the environmental cause by using the once discarded sawdust into a usable product.  A smaller carbon footprint also means buying local, so I have only listed local manufacturers.

I prefer to buy in bulk so the cost is comparable with firewood.   A pallet of the Renewable Heat Product’s bricks is about equal to a cord and one half of wood in cost and heat output.  I had the pallets delivered right to my house.  Here are some websites to find a supplier near you:

Bricks, Logs, and Scraps

Renewable Heat Products

Waterbury, CT


I sampled Hot Bricks and found it to be reliable and performed as advertised.  They have the Hot Brick in packs of 8 or 15, and can be bought in a pallet of 66 packs.  They also have the Hot Allnighter, which has the density and mass to last the whole night.  The Hot Bag of Fire is a burnable bag of CWF for a natural ambient fire.  Smaller packs are available at local retail and supermarkets, with bulk orders available for delivery by their local lumber supplier.


U.S Wood Recycled Products

Leola, PA



Millersburg, OH



Berlin, CT


The Wood Brick Fuel by US Wood Recycled Products, Eco Brick, and Bio Brick are other “brick” sized compressed wood fuels.  Smaller packs are available at local retail stores including lumberyards, farm supply stores, big box stores, supermarkets.  Bulk orders are typically available by delivery from local lumberyards.

If you need to buy a little, you can get it through most major and some local big box stores.  If you want bulk, talk to the manufacturer and see what options they have, or if any of their suppliers provide local delivery.

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