Paper Poised to Fill New Gaps as Insulation: Mirrorpanel May Mitigate Foam Flaws

Buildings account for 40% of energy usage in the United States. In a world that stresses increased levels of responsible energy use, ensuring that new and existing construction is as efficient as possible will be vital to meeting our nation’s sustainability goals. Wood has long been the material of choice for framing, walls, and floors, but designers often fall back on conventional foam insulation to keep the heat in and the elements out. New research however, published in Forest Products Journal, introduces an insulation system that may help give forest products the green light to fill in new gaps.

A cutaway of a Mirrorpanel revealing its layered construction.

The article, co-written by FPL Supervisory Materials Research Engineer Samuel Zelinka, and FPL Research Physical Scientist Samuel Glass, proposes a new type of insulation called Mirrorpanel. Mirrorpanel takes advantage of the low thermal conductivity of still air, and is made of closely spaced layers of coated paper in a wood or fiberboard frame. It has been fabricated and tested at the laboratory, wall, and building scale and was found to perform as well as its foam counterpart — so well that it would even meet the stringent 2012 International Energy Conservation Code (IECC) for continuous insulation.

Adding to Mirrorpanel’s appeal is its comparatively small environmental footprint. Conventional foam insulation is made using fossil fuels, and can have up to 24 times the environmental impact of natural insulation materials like cellulose or cork. A paper-based insulation like Mirrorpanel would mitigate this energy usage, and could even be made from recycled materials or low-value woody biomass clogging our nation’s forests and increasing fire danger.

The test house constructed using Mirrorpanels.

Paper-based insulation is not a new development in the forest products industry. FPL’s own Research Demonstration House, constructed in 2001, is insulated with a blown-in cellulose product made of recycled newspapers. It is the layered construction, IECC compliance and thermal efficiency, and scalability of the panels which puts Mirrorpanel ahead of the pack.

Although Mirrorpanel has been tested in house-sized structures, researchers caution that further development is needed for it to become a viable insulation system. More testing needs to be done, especially in regards to its moisture-storage characteristics, and economic feasibility. With the rise of environmentally friendly commercial construction, Mirrorpanel should also be tested at even larger scales to ensure it meets the requirements of large energy-efficient commercial buildings.

It may not be ready for prime time yet, but ideas like Mirrorpanel represent a step in the right direction for insulation systems, and embody what research at FPL is all about — the latest scientific research, promoting the health and sustainability of our nation’s most valuable resources, for the betterment of the American people.

For more information, please see Thermal Insulation System Made of Wood and Paper for Use in Residential Construction