Today’s homeowners are looking for ways to improve their home’s energy performance. A common problem with today’s homes is the “thermal bridging” effect – energy transfer through framing members that can rob a home of heat and waste energy and money.

To help validate insulated siding’s performance, VSI commissioned Newport Ventures to conduct the Insulated Siding Energy Performance Study to determine insulated siding’s effect on the energy performance of existing single-family homes under real-world conditions with a focus on building air tightness and heating energy use.

The ongoing retrofit study was initiated in fall 2010 and utility bill data will be collected over the next two years. Preliminary findings show: A 12 percent improvement in air tightness between the existing condition and post-installation of insulated siding.

A projected five to 12 percent improvement in the heating energy savings for the four homes post-installation of insulated siding based on simulations of pre-and post-insulated siding conditions. An improvement (reduction) of two to eight points in the homes’ HERS index through the installation of a water-resistive barrier and insulated siding based on building energy simulation results.

Download the full interim study here.