Masonry Magazine November 2007 Page. 18
GREEN BUILDING
Despite this misconception, more business owners, developers and consumers are calling for more energy-efficient buildings and sustainable structures. Americans don't want to just drive "green" cars, they want to live more environmentally aware, green lives. And they're backing up these desires with their wallets. According to the U.S. Green Building Council (USGBC), the green building industry is worth upwards of $12 billion. A significant portion of this growing trend can-and should be-masonry construction.
In this article, we'll explain how masonry materials are inherently green and how they can be incorporated into green building techniques. Additionally, we will profile various projects where masonry was used to help earn LEED credits.
As you likely know, the USGBC's Leadership in Energy and Environmental Design (LEED) Green Building Rating System is the benchmark for the design, construction and operation of high-performance green buildings. According to the council: "LEED gives building owners and operators the tools they need to have an immediate and measurable impact on their buildings' performance. LEED promotes a whole-building approach to sustainability by recognizing performance in five key areas of human and environmental health: sustainable site development, water savings, energy efficiency, materials selection and indoor environmental quality."
The MCAA says masonry can help with meeting LEED certification requirements "because of its many unique green attributes, several of which mirror the basic LEED program categories and include indoor environmental/air quality, daylighting, local material supply, heating and cooling features, and its renewable resource status." But masonry goes beyond the basic requirements "by aptly addressing such bonus or 'incentive' features as acoustic performance, increased fire safety, and the lowest life cycle costs. Masonry can satisfy the complete program," the MCAA says.
Further, according to the AIA's Environmental Resource Guide, the actual "embodied energy" (the energy required for raw material extraction, manufacturing and transportation) of the typical brick is about 14,000 BTUs, which is much less than the embodied energy of most other building materials, including concrete, glass, steel and fiber-cement products.
Brick should be a natural choice for builders in all categories who are concerned about sustainable design or who are trying
HEATING GREEN
By Norbert Senf
Masonry heaters are firing up green building practices. A masonry heater is a unique type of masonry fireplace that is able to burn wood cleanly. By rapidly burning a large batch of wood (up to 60 pounds), the heater stores the heat in a masonry thermal mass. The masonry then radiates heat gently into the building for up to 24 hours or more from a single two-hour firing.
Several aspects of masonry heaters tie in directly to green building, including greenhouse gas reduction, low output capacity and radiant heat:
**GREENHOUSE GAS REDUCTION**
Wood is a renewable fuel, particularly if harvested as part of a sustainable forestry operation. The downside of burning wood is air pollution. Wood potentially a clean fuel. Pollution from wood burning is almost entirely the result of incomplete (smoldering) combustion. It can be greatly reduced improved bum methods, and masonry heaters achieve this by burning the wood rapidly in a hot fire and then using the masonry mass to store the heat. Chimney flues have been known to stay clean for 20 years and long with proper operator practice.
**LOW OUTPUT CAPABILITY**
In a large, 8,000-pound heater, the heat from a two-hour burn of pounds of wood can be radiated into the building over a span of 24 hours at roughly 10,000 BTUs per hour. In many locations, this is a typical heat load for a superinsulated building on an average day. Other cordwood burning appliances have difficulty targeting such low heat loads without resorting to smoldering (dirty) combustion.
**RADIANT HEAT**
A typical large heater will have about 100 square feet of radiating masonry surface at about 150 degrees farenheit. This is widely regarded as a comfortable and healthy type of heating, similar to what is obtainable with a hydronic floor. There is minimal air movement, and a reduction dust circulation.
Norbert Senf is president of the Masonry Heater Association of North America.