A Net Zero Energy Home at Conventional Cost
Over the past three years of operation, the home’s baseline energy use has remained remarkably consistent — and remarkably low. The typical baseline energy use for the entire home is a mere 400W — less than many refrigerators. This includes all equipment that is always running: the Energy Recovery Ventilator, refrigerator, radon fan, and Internet equipment.
Continue reading “Baseline Energy Use: Running a House on $10 a Month”
The Iowa Nest Residence was recently featured in a presentation on Net Zero Energy buildings at the Trimble Dimensions conference in Las Vegas. Among other topics, the presentation covered the custom-built monitoring systems that measure temperature and relative humidity on an ongoing basis, as well as the eGauge system that monitors energy use at the circuit level.
As of August 2022, we have been monitoring energy use at the Iowa Nest Residence for three years post-occupancy. How is the home doing? How does it compare with our predictions and energy models? What lessons can we learn to apply to future ultra-low-energy designs? This post reviews the data and shares some observations and lessons learned.
Continue reading “Assessing Performance After Three Years of Operation”
The Iowa Nest was featured in the Phius webinar “Design Strategies for a Cost-Effective Passive House,” presented by Sanyog Rathod and Carl Sterner of Sol design + consulting. The webinar can be viewed free online here: https://www.phius.org/design-strategies-cost-effective-passive-house
Continue reading “Webinar: Design Strategies for a Cost-Effective Passive House”
The Iowa Nest Residence is featured on the SketchUp Blog as a case study in Net Zero Energy design. The article includes key lessons that were learned during design, including the importance of the overall shape of the home on performance and cost, and the importance of looking at passive measures and HVAC system holistically.
Continue reading “Press: Iowa Nest Residence featured on SketchUp Blog”
As of March 2021, the Nest Residence has already been through not one, but TWO polar vortex events — extended periods of extreme cold temperatures brought about by arctic air migrating unusually far south. In both cases, the home was operating without any mechanical systems running — presenting a unique opportunity to see how the home performs with passive strategies only. Here is how it did.
The design of this home was, in part, a test of a design process—of a philosophy of design—known as performance-based design. The central idea is that performance analysis (energy, daylight, and thermal comfort analysis, among others) has a central role to play in informing design decisions at every step of the process.
Continue reading “Designing a Net Zero Home: A Map of the Design Process”
What does it mean to be “comfortable?” This presentation at the DAAPx Symposium on Experiential Design in September 2020 uses the Iowa Nest Residence to explore the idea of designing for “thermal delight” (a term coined by Lisa Heschong in her book of the same name). It discusses how comfort is far more than just air temperature, and how these additional physical sensations were used in the Nest Residence to maintain comfort largely through passive measures.
The Iowa Nest Residence was featured on the cover, and in a feature article, of the May/June 2020 issue of ICF Builder Magazine. The issue focuses on green building, energy efficiency, and Passive House projects.
The Nest Residence won the 2020 ICF Builder Award in the category of Small Residential. The annual project-of-the-year competition is widely regarded as the biggest event in the Insulated Concrete Forms (ICF) industry.