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Check out our latest article on HEATING with masonry heaters and many other DESIGN articles below...

 

 

Heating your Timber Frame

What is a Masonry Heater?

A Masonry Heater allows you to heat your home with wood in a unique way. Its main distinction is the ability to store a large amount of heat. This means that you can rapidly burn a large charge of wood without overheating your house. The heat is stored in the masonry thermal mass, and then slowly radiates into your house for the next 18 to 24 hours.

If you burn wood fairly rapidly, it is a clean fuel. If you try to burn it too slowly, the fire will change from flaming to smoldering combustion. The burning process is incomplete and produces tars. Atmospheric pollution increases dramatically. This is important if you are planning an energy-efficient house. The average energy demand of your house will be quite low. For most of the time, it may require only 1 to 2 kW of heat. For most conventional woodstoves, this is below their "critical burn rate", or the point where they start to smolder. In other words, woodburning and energy efficient houses don't really suit each other very well, unless you have some way to store heat so that your stove can operate in the "clean" range all of the time.

Masonry heaters fill the bill perfectly. If you need even a very small amount of heat, such as between seasons when you simply want to take off the chill, you simply burn a smaller fuel charge-yet you still burn it quickly. The large surface is never too hot to touch. You have a premium radiant heating system with a comfort level that simply cannot be equaled by convection or forced air systems. MHA Masonry Heater Definition A masonry heater is a site-built or site-assembled, solid-fueled heating device constructed mainly of masonry materials in which the heat from intermittent fires burned rapidly in its firebox is stored in its massive structure for slow release to the building. It has an interior construction consisting of a firebox and heat exchange channels built from refractory components.

Specifically, a masonry heater has the following characteristics:

• A mass of at least 800 kg. (1760 lbs.),
• Tight fitting doors that are closed during the burn cycle,
• An overall average wall thickness not exceeding 250 mm (10 in.),
• Under normal operating conditions, the external surface of the masonry heater, except immediately surrounding the fuel loading door(s), does not exceed 110 C. (230 F.),
• The gas path through the internal heat exchange channels downstream of the firebox includes at least one 180 degree change in flow direction, usually downward, before entering the chimney,
• The length of the shortest single path from the firebox exit to the chimney entrance is at least twice the largest firebox dimension,
• A maximum chimney flue size of 200 mm X 300 mm (8 in. X 12 in.) nominal or 200 mm (8 in.) i.d. round, and
• The body of the masonry heater and its chimney do not penetrate an exterior vertical wall of the building.
  (passed unanimously at 1998 MHA Annual Meeting, June 8, 1998)

For Information on the Masonry Heater Association of North America:
http://mha-net.org/index.htm

One Cord of Firewood Conversion Values

4foot x 4foot x 4foot

• One Cord of Hardwood weighs 5,758 pounds
• One Cord of Pine weighs 5,232 pounds

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• One Cord of White Oak has 22.7 million BTU's
• One Cord of Hickory has 24.6 million BTU's
• One Cord of Red Maple has 18.6 million BTU's
• One Cord of White Pine has 13.3 million BTU's

Board Foot Conversion: 3.5 cords= one thousand board feet

Firewood Permits Available From U.S. Forest Service

 

Infloor® Heating Systems

 

 

Americans are changing the way they heat their homes...Starting in Minnesota and across the country to New Mexico, California, Ohio, Pennsylvania and even Florida.

Tim Ashenfelter and his family live in an 1890's home in Minnesota. When they decided to renovate their kitchen, they had to tackle an ancient, sloping floor, and their contractor told them that the only way to even out the floor would be to have a product called Therma-Floor® poured. This gypsum floor underlayment is a perfect conductor of heat, and the Ashenfelters decided to have radiant floor heating installed, too. Hot water piping was laid on top of the floor structure before the Therma-Floor was poured. "We can't wait for winter," says Tim Ashenfleter, "to see how our kids feel, walking across that warm floor in the middle of a cold Minnesota winter!"

When Terrance and Joan Fregley of Tallahassee decided they wanted the look of elegant marble floors, they also knew those floors would be chilly even in mild Florida winters. That's when they turned to radiant floor heating. "I wanted something to keep the floors warm during the winter." says Terrance. "In our case, radiant floor heating was a choice we made for its sheer comfort value. Our new floors not only feel good, they have added tremendously to the enjoyment of our home."

Bill and Lois Kempley have lived off the land in rural Wisconsin for more than 20 years. They have relied on every kind of heating system, including wood. When they decided to build a new farmhouse, they opted for electric radiant floor heating. "It's the cleanest, safest, most comfortable heating system we've every owned." says Lois. "It's invisible and so quiet. No forced air blowers to listen to and no ugly baseboards, registers or radiators to look at."

Kurt and Gerti Lausecker wanted every detail of their new home to be extra special. Kurt, who was raised in Germany with radiant floor heating, knew that he not only wanted the comfort of this heating system, he also knew first hand the energy efficiency of such a system. All 3,300 square feet of the Lausecker's new home is heated with radiant floor heating. "I can't tell you what a pleasure it is to be able to step out of our whirlpool onto a toasty warm floor," says Kurt.

The Ashenfelters, Fregleys, Kempleys and Lauseckers are part of a growing trend, nationwide away from forced air heating and toward radiant floor heating. "We are beginning to see a major expansion in the market," says John Fantauzzi, Infloor Product Manager at the Maxxon Corporation.

A leading American producer of radiant floor heating, the Maxxon Corporation is in Hamel, Minnesota. They developed a state-of-the-art group of products called Infloor® Heating Systems, that are now being installed by some 650 dealers nationwide. This is the way Infloor heating systems work. Hot water tubes or electric cables are attached to the subfloor and covered with a pourable floor underlayment called Therma-Floor®. Water circulating through the tubes or electrical resistance in the cables warms the underlayment and the floor covering. The floors never become hot, just pleasantly warm. Floor temperature is thermostatically controlled through a heat sensor inside the Therma-Floor or through an air sensor.

The concept can be adapted to any type of home. The hot water version can be connected to a boiler, water heater, heat pump, solar collector; basically any existing source of hot water. The electric version is equally adaptable. Increasingly, people are turning to radiant floor heating, both in the construction of new homes and when renovating and updating old ones.

Proponents of radiant floor heating -- and people who have switched from a standard heating system to a radiant floor heating system speak with a missionary zeal about their warm floors -- point out several advantages to the new heating systems. An Infloor heating system transfers heat directly; it doesn't waste energy trying to warm tremendous volumes of air, as in a forced-air system. There are no drafts or hot-air surges; heating throughout the home is uniform, with very little temperature difference between the floor and the ceiling. Utility bills for a home heated by radiant floor heating have a potential savings of up to 40% less than the identical home using a forced air furnace. Because heat doesn't collect at the ceiling where it is most likely to escape, radiant floor heating can also reduce heat loss by up to 30%. So even though your thermostat is set lower than it would be with a forced air system, you feel warmer. There are no registers or cold-air returns to circulate dust or allergens, and as homeowners and home buyers are becoming increasingly health conscious, this feature will probably become more important. Designers usually prefer to design homes heated with radiant floor heating because there are no ugly baseboards, no awkward radiators and no unsightly registers: nothing to interfere with interior furnishings or design concepts.

Though radiant floor heating is not a new invention, it is just beginning to catch on in the United States, with Minnesota, Colorado, New Mexico, Utah and Northern California in the lead. Radiant floor heating is well-entrenched in Europe, where an estimated 60% of existing homes, and up to 90% of new homes are heated through the floor. John Fantauzzi explains that "Europeans build their homes for the long haul. They expect their homes to be handed down from generation to generation, so when they build, they build for the future. They are willing to invest more upfront, for high quality systems that will last. In America, we tend to build houses we plan to live in for three or four years."

Asked why Americans have been slower to switch from forced air heating systems to radiant floor heating, sources in the housing industry invariably cite cost. The cost of installing radiant floor heating might cost two or three times more than a forced air system, initially. "And, 'initially' is the key word here," says Fantauzzi. "People who are building and buying new homes need to remember that in the long run, their heating bills will be up to 40% lower than they would be with forced air.

The other issue is quality. We believe that people will pay more for the added advantages of radiant floor heating: health, aesthetics, and more importantly, comfort. Just as people will pay more for a top-notch car that runs beautifully and lasts, over a cheap, inefficient one that constantly has to be repaired, they will pay more at the outset for radiant heating when they realize how comfortable it is."

One of the central reasons Americans have been slow to change over to radiant floor heating is that they have not been told about it, or, if they have heard about it, they have not experienced it. "Homeowners don't know how uncomfortable they are in a forced air heating system until they have experienced radiant floor heating," says Fantauzzi.

One way to try the comfort of Infloor is with a Warm Floor Kit. Infloor has a kit with everything a do-it-yourselfer (or contractor) needs to make floors barefoot warm. 120v electric cables attach quickly to wooden subfloors. The cables warm the Therma-Floor or mortar and floor coverings. Available in three sizes, the kits can be installed in bathrooms, kitchens, entryways or anywhere comfort is a priority.

Clyde Jorgenson, President of the Maxxon Corporation says, "There is a quiet revolution going on in this country. We see evidence of it every day, in the letters, phone calls, and orders we get from around the country. Americans are definitely changing the way they heat their homes."

For more information, contact:
Marketing Services Department,
Maxxon Corporation,
920 Hamel Road,
Hamel, Minnesota 55340.
Phone: (800) 588-4470
For even more information contact: Barbara Saxton (612) 478-9600

 

 

 

 

Passive Solar Design - Buildings for the Future

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

written in part by Stuart Perry, former NEED student from Rhode Island

People have observed the cycles of the sun for centuries and used that knowledge to heat, light, and even cool their buildings. But it was the oil embargoes of the 1970s that really started the country thinking about ways to reduce the energy needs of homes and other buildings. On average, 70 percent of buildings' energy costs are for heating, cooling, and lighting. How could we use less energy and less fuel-by designing buildings that maximize the sun's energy ?

Many researchers focused on designing buildings that use the sun naturally - or passively - without installing special equipment. Others incorporated solar panels in their designs to heat water and generate electricity. The early solar buildings did save energy, though they were too futuristic-looking for many people and not very cost-effective. The last twenty years, however, have brought innovations in window construction, insulation, and design that are making people take a second look.

In passive solar design, the idea is to collect light and heat energy from the sun during the day - maintaining a comfortable temperature inside and release the heat at night as temperatures drop. Think about climbing into a car on a sunny day, even when it's cool 'outside. It can be pretty hot in there, can't it ?

Sunlight enters through the windows and is converted to heat when it hits the interior. The same windows that let in the light energy keep the heat from escaping.

Passive solar - or climate responsive buildings are designed to take advantage of the sun's energy. Buildings are oriented with long, south-facing walls with many windows. Fewer windows are placed on north-facing walls. In addition, heavy floors and walls provide thermal mass to collect the heat, and advanced window systems prevent the heat from escaping, at night.

Good insulation in the walls and ceiling, and weatherstripping around cracks, are necessary to prevent heat loss in winter and to keep it out in the summer. The design and placement of doors is also important. Even the outdoor landscaping can make a building more energy-efficient.

With well-placed windows, the need for artificial lighting can be significantly reduced. Studies have shown that students perform better on tests when their classrooms have natural lighting and workers are more productive in solar office buildings. People also say that the heat in solar buildings is more comfortable than artificial heating.

Even older, traditional buildings use the sun s energy to some extent. Most buildings have windows that make use of sunlight to reduce the need for artificial lighting. And about five percent of a traditional building's heat comes from the sun.

These older buildings can be adapted in many ways to maximize the sun's energy. Installing- heavy, insulating shades on south facing walls is one way - and making sure that they're open during the day and closed at night in the winter. Adding an overhang to south facing windows can also make a big difference, since the sun's rays are more directly overhead in the summer and angled in the winter.

Another good idea is to plant deciduous trees near the windows. In the summer, the leaves shade the building from unwanted heat, while in winter the sunlight penetrates the bare branches to reach the windows. And, of course, increasing insulation and installing energy-efficient windows and doors always makes sense.

Every new structure built today should take advantage of the energy savings of passive solar design. Mary-Margaret Jenior, an expert on passive solar buildings at the Department of Energy, reports that new solar buildings in any climate in the U.S. can capture 40 - 90 percent of the energy they need for lighting, heating, and cooling. Researchers at DOE's National Renewable Energy Lab are designing building plans that use solar energy for 75 percent of their energy needs, without adding appreciably to the overall construction costs.

One of the most important developments in passive solar technology is the computer. With the help of an industry-government collaborative, the Passive Solar Industries Council has developed a software program that calculates the optimum design for a building, taking, into account the climate of the site and the materials and design strategies to be used. A similar program assists in integrating auxiliary energy systems in the buildings.

Adding- equipment such as photovoltaics is also advocated by many solar experts, now that the cost. efficiency, and reliability of PV cells has improved. Photovoltaics and active water heating systems can provide additional energy savings, but the cost may still seem prohibitive to many people.

Many researchers think that in the future, a well-designed solar building with occupants committed to conserving energy could harness all the energy it needs from the sun. "Maybe," says Mary-Margaret Jenior, "NEED students will say to themselves, 'my building could become the utility of the future!"'

Web sites for more information:

http://www.psic.org
http://www.nrel.gov/buildings/exemplary
http://www.eren.doe.gov
http://www.ases.org/solar

Suggested Activities:

1. Call your local builders association and ask if there are new solar buildings in your area and if any local builders are specializing in solar design. Take a field trip to one or more of the buildings. Ask a knowledgeable builder to speak to your classes.

2. Have groups of students design and build mock-ups of "the perfect solar home", incorporating the unique climate, materials, and energy sources available in your area.

 

 

Exemplary Living at the Grand Canyon

 

 

The recently completed environmentally friendly "exemplary home" at Grand Canyon National Park is the result of almost 20 years of buildings research. Designed by engineers of the National Renewable Energy Laboratory in conjunction with park service personnel, the home combines energy efficiency with state-of-the-art passive solar technology to achieve a 75 percent reduction in energy use compared with a conventional home.

"The occupants say they're very satisfied with the home's performance," said Todd Alexander, project manager for the National Park Service. 'Utility bills averaged about $100 a month in December, January, and February. Some of the other new homes nearby paid as much as $300 per month depending on the number of occupants and their lifestyle."

The exemplary home features glazed Trombe wall that captures and stores the sun's heat for slow, even release at night. On hot summer days, the Trombe wall keeps the home comfortably cool by intercepting the sun's heat. Clerestory windows bring natural daylight into the living space, reducing the need for energy-consuming electric lights. R-50 ceiling insulation, R-34 walls and an insulated concrete pad are part of an ultra-air-tight building envelope that reduces air leakage by 60 percent when compared to conventional construction. A waste heat recovery system captures heat from the ventilation system and uses it to worm the water for laundry, showers and kitchen.

"This is an integrated building design - one that considers all aspects of how a building uses energy," explains Paul Torcellini*, head of NREL?s exemplary buildings research program. "Typically, exemplary homes will cost about the same to build as conventional homes. Upfront design costs are a bit higher, but homeowners quickly recover the extra cost through energy savings."

Existing passive solar designs reduce home energy use by about 40 percent. Advanced technologies such as those demonstrated at the Grand Canyon have the potential to slash residential heating bills by as much as 95 percent and lighting bills by 80 percent.

This article first appeared in the July/August 1997 issue of Solar Today, a publication of the American Solar Energy Society, and is reprinted with permission of ASES and the writer, Linda Brown, a freelance writer in Colorado, who can be reached at (303) 838-1573.

*Paul Torcellini, head of NREL's exemplary buildings research program, is a former NEED student from Connecticut, and serves on NEED's Board of Directors.

Planning your Timber Frame

 

 

Is it Necessary to Buy a Sawmill?

When building their own homes, individuals frequently consider buying a sawmill to cut the lumber from their own timbers. In some cases, the expense is easily recouped. In most cases, it is best to seek other means to have lumber cut. One option is to have a local portable sawmill hired to saw at the site from the available timbers; and a second option is to compare this cost to the available beams and lumber available in the area. A sawmill will cost about $20,000, the maintenance is expensive, and generally a low return on the investment can be expected.

How to Choose Logs for Your Timberframe

When buying or cutting logs for a timber frame, it is very important to choose the ones most suitable for high-quality beams. Here are a few tips:

1. Never use logs that have a bow in them if you can avoid it. Bowed logs make bowed beams even if they are cut straight.
2. Do not choose logs with large knots. Large knots weaken the beam.
3. Do not choose logs that have been cut a long time ago. Pine logs will have beetle damage.
4. Watch for rot in the butt end of the log.
5. Make sure the diameter of the log is large enough for the beam you want. Remember any bow will reduce the size of the beam that is possible from the log.

 

 

What Type of Wood Should be Used?

The best choice of wood is based on several factors. The four most popular in the U.S. are White Pine, Douglas Fir, Oak and Yellow Pine. Personally, I think it is best to use the wood available to the timberframer you choose,. As for the "best" wood to choose, each has its particular qualities. For instance, White Pine is the most stable and Oak is the strongest.

Should my Beams be Planed or Not?

Determining whether to build your timber frame home of planed or unplaned beams is only a matter of taste. The planed timbers will come out with a very finished look. High end shops such as Thistlewood or the Upper Loft are well suited to build planed timber frames. The unplaned frame is a more rustic look. The joinery in an unplaned frame is never as exact as a planed frame. A company such as Cowee Mountain Timberframers prefers unplaned frames because they are more suitable for apprentice work as well as student workshops.

As for strength, remember that unplaned frames have been around for over one thousand years. Once again, it is only a matter of taste.

Buying Beams

One important factor which will affect your timber frame is the quality of the beams you buy from the sawmill. Check for the following:

1. What is the quality of the wood in the beam? Avoid large knots, wane on the edges and worm holes.
2. How square are the timbers? Always take a carpenter square when you buy timbers. Use your discretion with selecting square beams.
3. How old are the timbers? Old timbers that have been weathered may appear grey and very unattractive.
4. How straight are the timbers? Bowed timbers do not fit or square up in the pretrial assembly process.

 

 

 

 

 

 

 

 

 

 

Caring for your beams

When preparing to build a timber frame, nothing is more important than taking proper care of your beams once you receive them from the sawmill or the planer.
The three main things that harm timbers are sunlight, water and lack of air circulation. The best way to care for timbers is to have them in a well ventilated pole-barn style building. They should be on beams at least eight inches off the ground, level and placed in such a way as to give good support to your beams. Beams should be spaced about a half an inch apart. This allows air to circulate around the beam. After the first layer, you should place 1 x 1 or larger sticks between the layers. These should be placed directly above the 8 x 8 beams on the ground. Your stacks should not be more than 4 or 5 feet wide and no more than 4 or 5 feet high.
Note: You will have fewer problems with blue stain if your beams are cut in the winter.

Supervising Construction of Your Timber Frame Home

In some cases, supervising the construction of your own timber frame home can be beneficial. A great deal of money can be saved during the building process if you are able to:

• Manage your timber frame construction with a thorough knowledge of quality building techniques.
• Properly hire, schedule and supervise the particular subcontractors needed for your job.
• Organize purchases and deliveries of various materials for the appropriate subcontractors.
• Hold weekly meetings with subcontractors and other personnel (i.e. inspectors, delivery trucks, etc.) to coordinate work progress.

Note: It is recommended that you check references on unusually low bids.