Posts From April, 2019

HERS Raters: An Untapped Resource

These professionals can help with a lot more than inspections, but few builders understand that fact.
HERS Raters: An Untapped Resource
by Steve Byers According to RESNET, just 20% of new single-family homes have a HERS rater involved. When you consider that a rating is the most accurate way to gauge home performance, it's obvious that the industry has a long way to go. Even those builders who regularly contract with HERS raters seldom take advantage of the full value these industry pros can provide. That's unfortunate. The best raters offer more than code or program compliance: they're extremely cost-effective quality assurance partners. They can even help reduce a builder's liability for health and comfort issues, something today's overworked site supervisors seldom have time for. As CEO of a building consulting and training company with more than 25 years in the home performance business, I find that builders are more willing to take advantage of a performance-focused rater's services if they better understand how we work. The relationship is more like that with the architect or engineer than with the... read more
 

The Problem with HRVs

When integrated with the HVAC system, most E/HRV's don't deliver the desired ventilation air. A new design seeks to solve this problem, but we need your input.
The Problem with HRVs
by Srikanth Puttagunta, PE Builders believe that if they install an Energy Recovery or Heat Recovery Ventilator (E/HRV) they have ensured good indoor air quality. In reality, that's seldom the case. To deliver the needed fresh air, an E/HRV must be installed in a way that guarantees balanced airflows—where the intake and exhaust airstreams move equal volumes. But the design of these units makes proper installation difficult and, when integrated with the HVAC system (as most are), almost ensures that they fail to work as advertised. Of course, an E/HRV costs more than other ventilation strategies, so if it doesn't do what it's intended to, the builder has wasted that extra money. Steven Winter Associates is collaborating with a major manufacturer to develop an ERV that solves the shortcomings of conventional units. We have completed the second prototype. We hope to have a final design by Fall of 2019 with commercial availability sometime in 2020. Before moving to... read more