Accountability of Installed Performance

by Daniel Harkins

More stringent energy code requirements are coming for all conditioned metal buildings and other non-residential building types. Congress and the DOE have mandated a 30 percent reduction of energy consumption for the new energy conservation codes. The Energy Policy Act mandated all states must adopt a non-residential building energy conservation code and the ASHRAE 90.1 Model Standard was set as the minimum criteria a state could adopt.

On January 12, 2010, ASHRAE issued a press release (see www.ashrae.org ) with the proposed revised performance values of the traditional metal building insulation products, installed as they are typically installed. The existing U values being published in the ASHRAE 90.1 Standard since 1999 were found to be overstated, as the insulation is compressed during installation, and were not representative of actual performance as it is typically installed.

More importantly, a new method of predicting and verification of the installed performance of the installed compressed insulation products is also proposed for inclusion in the appendices of the new ASHRAE 2010-90.1 edition. There are now critical variables for purlin spacings and installed thickness which are required to properly evaluate such methods.

The effect of all of these proposed changes is that traditional metal building insulation methods that compress the insulation fall far short of meeting the minimum increased stringency of the proposed new 2010 Standard. They do not even meet the existing requirements in most instances. The installed performance will thereafter be able to be verified for compliance with reasonable accuracy. Different methods and assemblies that honestly perform will have to be employed.

It is long overdue that there will be accountability for the in-place thermal performance of compressed insulation methods. It is impossible for anyone to properly design an energy-efficient metal building and accurately calculate the heat loss and gains, when the insulation performance is substantially overstated and impossible to predict either before or after installation. These changes will assure the building owners actually get the performance and energy efficiency before they pay for it.

This will level the competitive playing field for honest competition of the various products . There will be big changes required to achieve the new stringency requirements and undoubtedly consequences for non-compliance. Everyone will benefit by closing this "black hole of performance" with accountability.

Daniel Harkins
Thermal Design
www.thermaldesign.com