Fireplace Designs that are Super Efficient

The fireplaces we are familiar with and take for granted throughout North America and most of Europe are extremely wasteful of energy when compared to some of the better designed fireplaces and stoves in existence. Granted, there are few things in life as nice as sitting in front of an open, roaring fire in the safety of one's home on a cold winter's day; however, the energy released from burning wood in this way is just exorbitant- it mostly escapes through the chimney. These fireplaces are also more dangerous than a lot of the more efficient models, both because sparks can easily fly out from the fire and ignite whatever they land on- a common cause of house fires and injuries (be sure to use a firescreen or door with such fireplaces). There are much better ways to put fuel (usually wood) for fireplaces to work, and the fireplace designs that get more use out of the same amount of fuel don't necessarily require more effort or money to build. Nor is it necessary to give up the delights of an open fire, though you will have to scale down a bit. Why not get the fireplace version of an economy car that runs just as well as, but is more cost-effective and friendly to the planet than a Hummer or other big, gas-guzzling SUV? This article presents some of these compelling, well-designed fireplaces in the form of the Rumford fireplace, masonry heaters including Finnish fireplaces which are also stone fireplace designs, and rocket stoves. Go beyond fireplace mantel designs and explore the guts behind some of the most ingenious fireplace design ideas known to man. We'll start with the one that's the closest to our wasteful fireplaces, the Rumford fireplace.

Invented by Sir Benjamin Thomas, who was born in 1753 and left Massachusetts for Britain after America gained independence in 1776, the Rumsford started out as an improvement of regular fireplaces. His design, introduced in the 1790s, made several alterations to the inefficient design of the fireplaces then in use by rounding off the entrance to the flue, giving the smoke a more unimpeded pathway to make its way out, making the actual fireplace shallower and with sides that opened out to the room for better heat radiation, and making it longer to have more surface area for heat to radiate as well. With these simple changes, efficiency is increased dramatically, meaning you don't need as much wood to keep warm. At the same time, the basic layout of normal fireplaces is intact and the fireplace is used in the same way. Another benefit of the Rumford is that fires are less smoky as the better flue design creates a stronger draw that is better at sucking the smoke out the chimney. It's a win-win situation if you really want that open fire because while it's not the most efficient way to heat your home, it is much more efficient than what most people currently use. The Rumford also doesn't have to be expensive if you are able to choose the fireplace design for your home. It may also be possible to retrofit an existing fireplace so that it is a Rumford fireplace. You'll have to check around to find a company that does this, however.

Masonry heaters are fireplaces that rely on a controlled burn and thermal mass. This means that the fire is contained and surrounded thickly by materials such as brick and stone. The fire heats this material, which is able to store the heat for long periods due to its mass (the efficiency of mass in storing heat is also seen in nature, where polar animals tend to be very large in order to use heat more efficiently- this is also why larger people tend to stay warmer than thin people in cold weather). After the fire goes out, the masonry continues to give off heat for up to 24 hours- all this from a fire that uses less fuel and burns for a shorter time than a fire in a normal fireplace! This efficiency does come with a price, however, as masonry fireplaces tend to be quite pricey. If you have the means, though, you can make up for it in the fuel you save and the steady source of heat also makes the investment worthwhile.
Perhaps the most advanced type of masonry heater is the Tulikivi, which is of Finnish origins. These fireplaces are constructed of soapstone, which is probably the natural material which is best at absorbing and storing heat. These work on the same principle and because of the ingenious design, make the fire burn super hot. This in turn causes the smoke itself to combust, yielding yet more heat and really making good use of the fuel. Because most of the smoke is burned up by the extra high temperatures, emissions are also reduced- a great ally in the fight against global warming (but very good for home warming:). Since these fit right in with contemporary fireplace designs, they are the best of both worlds in terms of aesthetics and functionality.

Finally, if the above choices are our of your price range, or if you appreciate highly functional designs, the rocket stove could be a perfect choice for your heating needs.  This ingenious design has seen most use in third world countries, but has also started to catch on in the United States.  It is not as attractive in a traditional sense as the previous two options, but its benefits are that they are cheap and relatively easy to build- you can perhaps build one for $100 in a weekend, according to at least one book on rocket stoves.  The rocket stove is the most efficient way to heat with wood at 90%, though some masonry heaters may come close or match this.  Rocket stoves consist of just three main component: the fuel magazine, which is a fancy name for the place where you put the wood, which is also where it feed into the combustion chamber, the part of the rocket stove where the fuel is burned.  Because the fire is sucked into this chamber, it is possible to use small diameter fuel like twigs and branches.  You can even use other dried plant matter like weeds if you just want to cook a meal- that's how fuel-efficient they are.  When used for heating, the best thing to do is to also use a thermal mass component as found in masonry heaters.  You can build one with free materials if you use cob, and the chimney can be run through, say, a built-in earthen bench, creating thermal mass that you can lay on!  Ianto Evans is a leader in the cob revival movement in the United States as well as proponent of sustainability- he is the author of the book "Rocket Mass Heaters: Superefficient Woodstoves YOU Can Build"- check it out if you think this is the right choice of fireplace for you.  Ianto has also written books on outdoor fireplace designs which are great for baking homemade bread and pizzas.