Climate change and a concern with how we consume energy is having big effects in the building industry. Our buildings consume a lot of energy and methods to minimise this consumption are being researched and developed all over the world. In 2010 a paper was written and presented by The National Renewable Energy Laboratory (NREL), a highly respected national laboratory of the U.S. Department of Energy - Office of Energy Efficiency & Renewable Energy that delivered findings that may have a surprising impact on how we build, now and into the future.
The research undertaken by NREL explored the thermal effects of metal fasteners in high performance buildings. The results of the research found that metal fasteners can reduce the insulation of a wall by as much as 3%. Think about that for just a minute.
Previously, all thermal modelling had neglected the effect of the metal nails and screws. In construction, advanced framing techniques provide better insulation but the effect of the metal was ignored. The metal causes a thermal short which results in the loss of thermal insulation and we now know, thanks to this research, that it can be as much as 3%.
The study (http://www.nrel.gov/docs/fy11osti/47678.pdf) measured thermal resistance values (R-value) across a number of different wall models with varying framing factors. It found that the R-value decreases by 3.3% to as much as 12% dependent upon a range of factors. They developed an adjustment equation that can be used in conjunction with common measuring techniques that had a high degree of accuracy, so that builders can more accurately measure the thermal resistance of their construction and finally take into account the metal fasteners. But there’s an even better solution.
Polymer fasteners won’t have the same effect that metal fasteners do on thermal insulation. Unlike metal fasteners, polymer fasteners have similar thermal qualities to wood and won’t create the same area of thermal weakness, providing better or superior insulation. In addition, polymer fasteners have other benefits such as no corrosion, oxidation or rust and have a much higher tensile holding power than metal fasteners. Polymer fasteners also don’t damage equipment. They can save time and money and now we know that they can also provide a higher thermal insulation measurement.
Braford Industries supply polymer fasteners to the Australian and New Zealand construction and manufacturing industries. If you’re in the business of building eco-friendly dwellings, then you need to seriously consider changing to polymer fasteners.