History of Cellulose Insulation
To understand new trends in cellulose insulation and energy efficient building, it’s useful to look at how it all started. In its simplest form, insulation began when the first cavemen shielded themselves from the elements. But it took thousands of years before the idea of adding material between the interior and exterior wall caught on. In the United States, the first architect who used insulation was Thomas Jefferson in his design of Monticello. And the insulation he used was cellulose.
The term “cellulose” refers to the base fiber for all plant life. Wood, paper and other plant-based products all are cellulose materials.
Today’s cellulose insulation is made from recycled paper products and treated with boron-based chemicals to make it fire retardant. But in Jefferson’s day and throughout history, choices about materials were driven by the ready availability of raw materials and their byproducts. At the turn of the century, the available material was wood, so insulation was balsa wool or balsa batt – sawdust encapsulated in a paper package. To this day, balsa wool insulation can be found in old, historic houses in the Northeast.
In the 1930s, a byproduct from U.S. steel mills – rock metal slag – provided another insulation product. It was heated to a liquid state and fiberized, and the end product was rock wool insulation. The same process was used to create insulation from another common material – sand, or silica – and the result was fiberglass. Similarly, as the U.S. paper industry grew, it was only natural to look to paper byproducts for insulation. Originally manufactured as a sound deadener, paper-based cellulose soon caught on as an effective, dense insulation material. But early cellulose insulation didn’t benefit from today’s fiber technology and application equipment, so it remained a small portion of the market as fiberglass became increasingly popular after World War II.
When the energy crisis hit in the 1970s, demand for insulation reached an all-time high and a resurgence of interest in cellulose insulation followed. The industry grew rapidly but it was a boom mentality with more than a few opportunists. Once the energy panic subsided, the cellulose industry experienced a shakeout and again settled into a relatively small share of the market.
The companies that remained, however, were deeply committed. They continued to refine the material, the application techniques and the manufacturing processes. And, perhaps most important, manufacturers and their customers remained convinced through their experiences that cellulose is great for most of insulation jobs.
In the 1990s, it was interest from the building science community and advocates of energy efficient building that led to scientific studies reinforcing what the cellulose insulation community intuitively knew to be true all along – that today's non settling, fire retardant, cellulose insulation has important performance advantages. This brings cellulose massively as well to Europa.
Today, as in the past, energy efficiency remains a vital concern
for building owners and the entire Nation.
Since the "Energy Crisis" of the mid-1970s sent heating and cooling bills almost into orbit homeowner's have appreciated the value of well-insulated homes.
Although energy cost increases has stabilized, there are still many compelling reasons for energy-efficient homes.
In fact, effective energy conservation is one of the factors
that has helped hold down energy prices.
In the 1990s, as first demonstrated in the mid-'70s, adequately-insulated homes not only save money for homeowner's every month; they also help America conserve vital energy resources for the future, and help keep the "demand-pull" factor from forcing energy prices higher.
In addition, energy efficient buildings help the environment through lower rates of atmospheric pollution emissions from power plants and on-site combustion of fuels for heating, air-conditioning, and ventilation.
Cellulose Insulation today
Cellulose insulation is produced from recovered wood pulp, primarily recycled newsprint. In spite of the growing production and use of paper products with recycled content, waste paper remains the single largest waste disposal problem for most communities.
Greater use of recovered materials in the construction industry can make an important contribution toward mitigation of that problem. An important benefit of cellulose as a use for recycled newsprint is that most cities have nearby cellulose plants. This means the waste material is converted close to its point of origin, eliminating the need to ship it long distances to landfills or drinking plants.
Cellulose insulation may appear to be a rather low-tech approach to energy conservation. In fact, today's cellulose products are extremely sophisticated, and represent decades of research and real world experience. Material density of loose-fill cellulose is one example of the progress that has occurred. As recently as 1980 the settled density of a typical cellulose product was over 42kg/m3. By the mid-80s average density had decreased to about 40kg/m3. A couple years later 38kg/m3 was common. This was done by improving and refining production technology that had been used for 40 years or more.
At the end of the 1980s new manufacturing technologies became available, and the density of cellulose insulation dropped suddenly by about a 2-5kg/m3. Today the average settled density of cellulose is about 30-35kg/m3. There are many products available.
Cellulose wall cavity spray has been available since the 1970s, but costs and the small number of qualified contractors limited this product to luxury homes. Today cellulose wall spray is a viable option for any home, and its superior energy-saving performance will pay back the slightly higher cost within a year or two. Today's spray-on products are formulated for application with very little added water, and the application system is designed to permit rapid installation. Because of the low moisture content, the wall can be closed very soon after the insulation is installed.
Other options for wall insulation are proprietary systems that use various permanent retainers to hold the insulation in place, and movable jigs that clamp onto the wall(as well in home production factories), creating a temporary cavity that's dense-packed with dry cellulose. There are also retainer systems that make cellulose a viable option for insulating cathedral ceilings and crawl spaces.
Cellulose insulation is now produced on very good technology based on fiberization systems, which maximize fiber separation. These attenuated, long and slender fibers are consistent, uniform and offer much better comfort during application. The low settled density (30-35kg/m3) thermal resistance (lambda value usually from 0,38-0,40), have consistently added profits and market share for many manufacturers.
There are some advantages compare to older technologies producing cellulose:
- 6% higher resistance to heat flow
- 30% lower density
- 30% less storage space required
- significantly less dust
- fewer application problems
- 25 % faster installation
- increase your revenues and save your customers money at the same time
Today cellulose insulation is optimal solution for you house.