E3 recently completed a project in the Forrest Hills area of Nashville, TN.

The homeowners reached out to E3 about mold and indoor air quality concerns. One of the homeowners is a musician and spends a lot of time in her home studio creating music. The couple also has plans to build a family and wanted to create a space that is healthy and safe. 

The homeowners are also very aware of their environmental impact and strive to live a sustainable lifestyle. They recognized that their home represents their way of life, and it was not nearly as sustainable as they wanted it could be. 

The classic Robert Anderson home sits atop of wooded hill in the Forrest Hills area, like a tree house. The home has a natural sense of serenity, and with the windows and doors open on a beautiful spring day, bird sons fill the large open living room. No wonder a musician picked this place to create music!

Unfortunately, the air quality and the energy bills painted a different story. 

The home was purchased in 2015 and the homeowners were concerned about the underbelly smell of the house permeating up into the entry way and living space. They knew one of their HVAC systems was about to die and wanted to make the home “as sustainable as possible” during the process of replacement. They noted that they already had solar panels and electric cars; now it was time to upgrade the house! In the words of the homeowner: 

I feel it's responsible to make improvements to that are helping 
reduce our footprint and provide a clean healthy indoor
environment and help us prepare for a more rugged future. We want to uphold the integrity of such a unique and beautiful home.

After the E3 Healthy Home Diagnostic Assessment, which included an ERMI test, E3 found a number of home performance concerns. The ERMI results indicated high levels of mold-related particulate matter, which the homeowners were already suspicious of. The primary source was the inside of the HVAC system. Mold needs water to grow, and HVAC systems produce water when in cooling mode. As you can see from the photo below, the interior of the HVAC system was not clean and showed a lot of evidence of moisture (rust!). E3 found a number of other concerns that were contributing to poor indoor air quality and excess energy use.

This spurred the homeowners to take action! They worked with E3 to create a plan that would improve comfort control, air quality, efficiency and durability.  

New HVAC Systems

The homeowners wanted to electrify their home, so all-electric Mitsubishi HVAC systems was installed to maximize the benefit of their solar generation. The new design allowed for independent temperature control in four areas of the home: main floor, master bedroom wing, guest bedroom and office wing, and basement studio. The performance was optimized, and the tonage was reduced from 13 tons down to 8 tons, which will significantly reduce energy cost!

In addition to the HVAC systems, new clean duct work was also installed with an extra layer of filtration to keep the air and the HVAC system clean. 

An ERV was installed to supply the home with fresh air and the bathroom fans were upgraded to operate automatically when the bathrooms were in use. 

Insulation

Spray foam insulation was added to areas of the home that needed both air sealing and a better thermal barrier. Air sealing and insulating the home allowed the HVAC systems to be sized smaller than the pre-existing units, saving energy and carbon emissions. R-49 insulation and a radiant barrier was added in other parts of the home. 

Crawlspace

The crawlspace/unfinished basement was unsealed and showed evidence of water damage. It was the source of the smelly sock smell the home experienced during wet rainy periods. Sealing this space with an encapsulated crawlspace system and adding a designated dehumidifier reduced the moisture load on the home and took care of the sour odor. 

Lighting

This home was primary lit with the original can light fixtures. The old incandescent light bulbs in these fixtures, and the fixtures themselves are inefficient giving off a lot of heat and contributing to air leakage. The lighting upgrade in the living room and master bedroom optimized the light direction and control switches and provided much improved energy efficiency.

Bonus Room

The new bonus room was spray foamed and equipped with Velux skylights to bring in natural light into a dark space. This new room was designed into the load calculation for the new second floor HVAC system. This space was left at the drywall stage, as the homeowners plan to complete the finishing process themselves in the near future. 

TVA Energy Right

After the renovations were complete, the homeowners opted to have the electric utility provide a TVA Energy Score. Their home received a 9 out of 10! The homeowner mentioned: 

We just had the TVA people come by and they said this is the "best house they have seen yet" in terms of the work [E3] did with HVAC, improved air quality and sealing envelope, fans, lights, AirThings, etc….!

 Their home scored a 10 out of 10 in the following areas:

The next steps to get to a 10 out of 10 will be to: 

• Complete the lighitng retrofit in the remainder of the home
• Update appliances and electronics with ENERGY STAR models when the time comes for replacement

In conclusion... 

Improvements included:

• 30% reduction in home infiltration
• 56% improvement to exhaust flow rate
• 90% reduction in duct air leakage
• ~40% reduction in HVAC capacity
• Cleaner air and fewer particulates with added filtration and fresh air ventilation
• BONUS: ~200 SF of new living space and a new lighting design throughout home.

The homeowners are loving their newly upgraded home!

We have most definitely noticed a different sense in the house!! It is significant. Peaceful. The house isn’t having to work as hard, so things are more consistent temp wise and quiet operationally. The new fans look great and contribute to that good air flow and the new paint and lighting looks really great - especially loving the wall lighting and the way it disperses light into the rooms and doesn’t interfere with the fan movement, and the warm vibe of the new LED's. And most definitely a better smell in basement and first floor!! All of these combined makes it feel like a new home in many ways. I am still taking it all in - it’s very significant the shift. Very exciting - we have much gratitude. It’s the kind of stuff that people don’t know they are missing until they experience it!

- Mary Kate

Are you ready to create a high performance, energy-efficient, healthy home? 

Give E3 INNOVATE a call today to get started!

615-876-5479