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Sustainable Construction: Has it Reached Critical Mass?

by Norbert Senf

This article first appeared in Volume 7 Number 1 of MHA News, Spring 1995


The First International Conference on Sustainable Construction was held in Tampa, Florida, November 6 - 9, 1994. Sponsors included Environmental Building News (see MHA reciprocal member list), Rocky Mountain Institute (home of soft energy paths advocate Amory Lovins), the University of Florida, and CIB - International Council for Building Research Studies.

An international group of researchers presented about 150 papers, and about 300 people participated in the conference. The Conference Proceedings are available from the University of Florida (885 pages, $100 US)

Keynote speaker Paul Hawken stated that in the year since the publication of The Ecology of Commerce, his most recent book, he has become convinced that the sustainability movement has reached critical mass.

See the separate report on Hawken's ideas elsewhere in this issue.

Keen Interest in Masonry Heaters at Trade Show

The conference included a small trade show with 30 booths. Masonry heaters were present with an MHA booth hosted by my wife Leila and myself, using the generic photo display put together by Lou Frisch. Interest in masonry heaters was the highest of any show that we’ve seen. The attendees were well qualified and included a high proportion of architects, architecture professors and builders who were specifically looking for “green” products. We soon ran out of MHA brochures and newsletters.

Masonry heaters were in excellent company at the show. Our booth neighbour to one side was Collins Pine Company, owners of the first forest in the United States to be independently certified for its impact on the environment. Since sustainable forestry practice can yield large volumes of firewood, it is a perfect complement to environmentally responsible woodburning. Certified sustainably grown firewood is available in Germany, pushed by demand from educated consumers. Our neighbour to the other side, from Germany, was Hebel aerated concrete, “both environmentally and structurally sound”, and now manufactured in the United States. We felt very much at home at this show - there were no fossil-fueled fireplaces to be seen.

It is important for masonry heaters to become more visible in the sustainability arena. Very clean (as opposed to merely “EPA clean”) biomass technology, such as ours, has an important contribution to make. Sustainable construction is only now approaching critical mass, and consensus is only starting to be approached on many of the concepts. Energy efficiency certainly is the key. Embodied energy is an idea just beginning to gain widespread popularity. On the heating side, we don’t really see much offered yet. This is probably because the recent cheap oil era has given us a sort of collective amnesia about heating. Heating is now automatically associated with fans, pumps and controllers - it has become the domain of the mechanical engineer. It is our job to start challenging some of those unconscious assumptions - we’ve got some good cards to play.

Defining Sustainability

The conference was split up into 13 sessions. Sessions 1 and 2 addressed “defining sustainability”.

What does sustainability mean? The idea of trying to live a sustainable lifestyle and designing a sustainable economy means that we need to start behaving as if we would like to have great-grandchildren and beyond. To North Americans in particular, it is a wakeup call. It is becoming quite clear to increasing numbers of people, including a lot of masonry heater builders, that we are living in a fool’s paradise if our only guiding principle is “business as usual”, with perhaps the hope of a techno-fix or two. We need to redesign our economy and our businesses and figure out how to make a good, enjoyable living off annual solar income, instead spending our principal and compromising not just our own future, but also that of the global ecosystem. Viewed from the international perspective of a conference such as this, it soon becomes obvious that a majority of North America is asleep at the wheel. We live the lifestyle of addicts. Ridiculously cheap energy is our drug.

Conference organizer Charles Kibbert kicked off the discussion of defining sustainability at the conference and presented the following comparison:

Traditional Criteria

  • Performance
  • Quality
  • Cost

Sustainability Criteria

  • Resource depletion
  • Environmental degradation
  • Healthy environment

Embodied Energy

One of the main threads to emerge at the conference was the concept of embodied energy content. Embodied energy includes the amount of energy used in the manufacture of the materials. For wood, it also includes the energy content of the wood itself, which is classed as renewable. An Austrian paper reported that, in some buildings studied, the embodied energy in the building was equivalent to about 40 years worth of annual energy consumption.

Embodied energy analysis is a new field. The flavour of some of the current research can perhaps best be illustrated by an example from a paper presented by Tarja Häkkinen, chief research scientist at VTT, the Finnish Building Technology Technical Research Centre. The paper is titled “Environmental Aspects of Building Materials” and gives the following detailed analysis for some timber products:

Embodied Energy Content Analysis For Three Construction Materials
Material or Energy Emissions or use of raw material per kg product (dry material)
Structural timber Roof truss Cladding boards
CO2 95.7 g 98.4 g 94.1 g
CO 5.91 g 8.33 g 5.83 g
NOx 3.39 g 4.02 g 3.34 g
SO2 0.112 g 0.121 g 0.110 g
VOC total 1.16 g 1.56 g 1.14 g
CH4 0.415 g 0.552 g 0.409 g
PAH 0.00123 g 0.00175 g 0.00121 g
Benzene 0.0341 g 0.0474 g 0.0336 g
Other VOCs 0.700 g 0.915 g 0.690 g
Heavy metals 0.000478 g 0.000679 g 0.000471 g
Dust into air (particulates) 0.773 g 1.06 g 0.761 g
BOUND CARBON (CO2) 792 g 792 g 792 g
Wooden raw material (wet/dry) 4900/2660 g 5400/2940 g 4830/2750 g
Phosphate fertilizers 0.300 g 0.331 g 0.295 g
Nitrogen fertilizers 1.71 g 1.88 g 1.68 g
Potassium fertilizers 0.300 g 0.331 g 0.295 g
Pesticides 0.0173 g 0.0191 g 0.0170 g
Saw blade chain oil, biol. 0.0628 g 0.0691 g 0.0617 g
Saw blade chain oil, miner. 0.128 g 0.141 g 0.126 g
Lubricants, biol. 0.246 g 0.271 g 0.242 g
Lubricants, miner. 0.917 g 1.01 g 0.902 g
Steel bands 0.790 g 0.870 g 0.780 g
Wrapping 2.11 g 2.32 g 2.08 g
Stamping colours (latex) 0.0135 g 0.0380 g 0.0133 g
Blue stain prevention 0.320 g 0.350 g 0.310 g
Nail and nail sheets 6.22 g 42.2 g 7.22 g
Paints - - 201 g
Renewable energy (Higher Heating Value of logs) 54.6 MJ 60.2 MJ 56.5 MJ
Fossil fuels 1.40 MJ 1.38 MJ 1.38 MJ
Electricity 0.0140 MJ 0.0100 MJ 0.00695 MJ
Utilization of waste heat 0.208 MJ 1.21 MJ 0.205 MJ
Potential energy
of products 17.1 MJ 17.1 MJ 17.1 MJ
of loss at building site 2.61 MJ - 4.95 MJ

I asked Ms. Häkkinen whether a similar analysis has been done for masonry materials. She replied that it hasn’t. The masonry industry in Finland is considering it, but hasn’t yet decided to do it.

Other Factors:

Dr. Kibbert went on to suggest the following scheme as a starting point for assessing the sustainability aspects of the building process:

  • Embodied energy content
  • Greenhouse warming gases
  • Toxics generated/content

He warned that translating this from an academic discussion into the real world is fraught with complications. A repeated comment that I heard many times on this topic was that our current database is inadequate - the real homework is only starting to be done in this area, but research is growing rapidly. I learned, for example, that US-EPA is planning to put an online database on the Internet within two years that will give access to such things as embodied energy information for building materials and processes.

Masonry Heater Builders Take Note:

North American heater builders who can offer an analysis of their product will thus have an automatic edge on the Infobahn. Another major shift for EPA will be a change in their mandate to focus on pollution avoidance rather than an “end-of-pipe” approach to toxics as is now the case.

Heater builders should take note, because pollution avoidance is something we are very good at. So far, we’ve been getting smacked with the same stick as the woodsmoke culprits. We’ve been forced into a position of defending ourselves (reactive) rather than getting the credit for cleanburning that most of us can rightfully lay claim to (proactive). This hasn’t been entirely bad, since it forced our industry to take a hard look at emissions issues and has in fact resulted in cleaner masonry heaters and in ongoing improvements.

If we want to be serious players in this arena, however, we’ve got to move beyond merely making claims that often are unsubstantiated and make a long-term commitment to educating ourselves in this field. Our clients are using more sophisticated criteria all the time in making their choices. Most of them are well educated and research their heater choice extensively. One manufacturer recently told me that purchasers are often more informed about heater issues than some of the dealers. The heater builder who builds up the most expertise will have a head start. This means education and training. It also means engaging in and supporting research. And it also includes networking with fellow builders and building our collective knowledge base.

When the EPA database and others come online on the Internet, where will masonry heaters be? Will manufacturers and builders be ready to make their case to the public? Can you formulate an environmental impact statement for your product and your business? We have an excellent product in many cases and can make a good case, and the playing field right now is fairly level inside the wood heating industry itself (although far from level when it comes to fossil fuel). More and more people are just beginning to consider these things in depth. The analogy with sports should probably stop here, because the winners will be co-operating with the other players, rather than trying to beat them into the ground. In many cases this will be a bottom-up process with smaller companies leading the way. A sizeable chunk of MHA members are doing this already, and have been for years - there are interesting, fun times ahead.

Other Events:

The list of papers presented at the conference was large, almost overwhelming. I’m still trying to digest much of it, but earning a living keeps interrupting. A presentation by Paul Hawken had the most impact on me, and is described in more detail below. Here’s sampling of other presentations:

Environmental Building News: This 20 page bi-monthly newsletter seems to be one of the most influential publications in the field. MHA members will recognize the name from our Associate member list. Managing Editor Nadav Malin led a workshop on the pros and cons of various building materials that was extremely well received. Low key and articulate, he picked the audience’s brains on their knowledge of various building materials with the help of a simple slide show. It was a fast education for everyone, and the knowledge of many of the audience members was astonishing. A number were leading edge builders who have to deal with toxicity of building materials and liability issues on a daily basis. Many of them are pioneering the use of new materials in the workaday construction world (a lot of parallels with heater builders here) and have to be on their toes continously. For example, one discussion centered on a new type of insulation consisting of batts made from cotton instead of glass fibre. Many people had had experience with it, knew particular details about manufacturer, availability and supply problems, as well as performance details. One builder had a house ignited by a plumber’s torch because a faulty lot of the insulation didn’t have adequate flame retardant chemicals. Others knew what the current status of the product was. This type of spontaneous networking and sharing of information was typical of much of the conference.

What became obvious here is that many of us in the “construction industry” are making the move into an information economy. Spending money to attend a conference is a good example. As Steward Brand has stated, the paradox of information is that it both wants to be expensive and free at the same time. Most of us have some expensive lessons under our belts, yet it is a thrill to share and swap them with colleagues. Information about the lesson, duplicated and given away, gains in value. In addition, we also have a new market out there of enlightened clients looking for efficient, non-toxic, low-environmental impact buildings. Often these buildings can be lower in cost, because it may involve leaving things out, such as carpeting and other surface finishes. Viewed from the right perspective, even a masonry heating system is low cost - perhaps even compellingly so. Price and cost are two different things. So are talking and doing.

Environmental Building News was one of the sponsors of the conference. The publication is respected, often by parties on both sides of an issue, because of the thoroughness of its research and the even-handedness of its reporting. It is considered essential reading by many members of the sustainable building communinty in North America and elsewhere. They know about masonry heaters, for example. By the same token, we all need to know more about how masonry heaters fit into the larger picture of appropriate construction. Subscriptions are $60.00, available from EBN at RR 1, Box 161, Brattleboro, VT 05301; 802/257-7300; FAX 802/7304. They need your support so that they can continue and expand their valuable work.


“Design Method and Tools For Sustainable Construction”, presented by Pekka Huovila, VTT Building Technology:

“Sustainable development has a long tradition in Finland. Our national epic poem, the Lakevala, published in its final form in 1849, based on material that goes back to the first millenium of our era, describes the felling of trees for growing of barley and oats as follows:

He cut down all the fine trees
but he left one birch
to the birds’ resting place
and the cuckoo’s calling tree

So were set the first written design guidelines for sustainable development 150 years ago. The challenge of sustainable development has also been taken as a starting point in the Finnish Building Law:

“An area to be planned or its use must be planned in such a way that the planning will support the sustainable development of the natural resources and of the environment”.

Mr. Huovila described several projects at VTT, including a 5 yr, $20,000,000 program to develop new design tools. For one such tool, known as ECO-CAD,

“the objective of the project is to apply existing knowledge rapidly in use through developing a simple tool that gathers basic information of building parts from building designs, their corresponding environmental information for material, component and production databases, calculates their cumulative environmental impact and gives the ecological profile as output”. Also described is Design For Environment (DFE) in product development:

“Following the Dutch National Environmental Policy Plan, which is based on sustainable development (van der Horst et al, 1994) to obtain environmentally improved products one has to choose for higher quality and innovation first. Next, the least input of resources can be attained by closing the material cycle; reduction and selectivity of material use; preference for renewable and recyclable material; saving of energy as much as possible. Finally, minimization of hazardous waste, especially toxic emissions, has to be striven for.”

Some of the other papers:

Ancient solutions for future sustainability: building with adobe, rammed earth, and mud - Michael Moquin (USA)

Site design and planning for sustainable construction - Kim Schaefer (USA)

Pressed soil-cement block: an alternative building material for masonry - B.V. Venhakatarama Reddy (India)

Construction and demolition wood waste used in wood cement composites - Robert Frank (USA)

Plastered straw bale construction : A re-discovered vernacular building system - Maire E. O’Neill (USA)

An appraisal of the deciduous roof - J.S.C. Evans et al (UK)

The use of recycled high density polyethylene fibers as secondary reinforcement in Portland cement concrete - Flynn L. Auchey (USA)

Construction waste and a new design methodology - Richard C. Hill, et al (Australia)

Ekotecture: an integrated approach to sustainable construction - Lee P. Butler (USA)

Understanding ecological changes in the Danish building tradition - Kim H. Hansen (Denmark)

Quantification of construction and demolition waste - Robert L. Christensen (Canada)

The green material index - development of an environmental auditing system for building materials - David E. Shiers et al (UK)

Possibilities of reusing construction waste: a feasibility study for the city of Vienna 1993 - Peter Maydl (Austria)

Geonomics: fostering a market for sustainable building by reforming taxes and subsidies - Jeffrey J. Smith (USA)

Developments of new type of reinforced concrete composite using high flexural strength surface forming materials for solving environmental problems - Takaaki Ohkubo et al (Japan)

Using waste materials as an aggregate in low thermal conductivity mortars - John A. Tinker et al (UK)

Suggestive concepts and new developments of earth conscious methods for constructing reinforced concrete structures - Akio Baba et al (Japan)

Newly developed reinforced masonry structures suitable for global environmental requirements - Miho Makatayama et al (Japan)

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