An Uncomfortable House with a Perfect HVAC System

I entered a home recently that I’d been to before. The complaint was super high energy bills. Years ago, I had renovated the HVAC system and rated the system at an operating efficiency of 100%. It was one of the best systems in the country. The duct system was perfect, less than a degree different upstairs to downstairs. But the Utility bills in this 1900-sq.-ft. home exceeded $400 per month this winter. Something was up. It was my job to find the problem.

Higher Electric Rates

The home was being remodeled several years ago when we renovated the HVAC system, and currently an update of the kitchen was underway. A discussion at the kitchen table revealed a recent change in the electric rates in the neighborhood. A 30 year discounted rate for one of Ohio’s first all electric subdivision had expired, doubling the cost of electricity. We discovered the low rates had disguised a number of deficiencies in the house that we missed previously.

HVAC System

Actually, the electric bill had dropped by 50% after we had installed new HVAC equipment. We also added a large new return, three more supply ducts, beefed up duct insulation to R-19 and had applied foam insulation to the ducts near the equipment. We replaced registers and grilles, installed a new thermostat, added dampers, balanced the system, and adjusted the refrigerant charge.

Since comfort was ideal and the electric bill was low, we quit looking for problems and called the house efficient.

Melted Snow on the Roof

I couldn’t help but notice when I arrived after a fresh snow, that the roof wasn’t all white. In reality it had half of the shingles showing and the house had some gorgeous three-foot icicles. I thought these were really cool when I moved to Ohio 10 years ago, but since have learned they are evidence of a poor insulation job.

I pulled out the infrared camera, scanned the house from the outside and identified several huge thermal bypasses. Further images found two massive building cavities around the fireplace. Interior shots with the IR camera revealed a 2-ft. x 3-ft. uninsulated combustion air chase below a large fireplace that was the reason for a handsome pile of blankets and pillows in one corner of the living room.

Cold Floors in the Bathrooms

A discussion about comfort ensued. It was mentioned that the floors in the upstairs bathrooms were cold. The ceiling happened to be open in the kitchen to prepare for new lighting, so we took a look together. An inspection and a few shots with the infrared camera revealed a significant problem between the first and second story of the home. There was no insulation at the outside walls.

The original builder installed a ¾-in. thick fiberboard behind the cedar siding of the home for insulation. We shot a soffit in the kitchen with the IR camera and found cold pouring in from the outside, which meant zero insulation there.

The Attic

It was 20F outside and we knew an inspection of the attic was essential at this point. We opened the closet to the attic access in the upstairs bedroom and were met with a blast of air fifteen degrees colder than the comfortable air in the room. The attic hatch was an uninsulated piece of ¾-in. plywood that barely filled the attic access hole.

A quick look around the attic made me grin at the gorgeous duct system. But I felt my face frown when I spotted eight new can lights, some with as much as four square feet of attic insulation missing around each new light.

The infrared camera view was filled with bright red and yellow splotches as we found a dozen stud joists between the vaulted ceilings and the roof bellowing heat from the house below.

Water Heating

Further discussion about comfort and efficiency uncovered another problem; a short supply of hot water. The husband complained a single shower could drain an oversized electric water heater. I felt the supply water line to the water heater and it came directly from the frozen ground outside.

More to Come

A quick test confirmed the HVAC system was still operating in good form. But it was clear that the energy problems were real and significant. I’ve called a few subcontractors in for further consultation and am anxious to report on the progress of this home. It will be interesting to get down to some hard facts.

Bottom line is that we have an uncomfortable house with a perfect HVAC system, but we still have significant comfort issues and energy hogs lurking all over the home. This inspection was a good start, but I’ll be writing more about this house.

Rob “Doc” Falke serves the industry as president of National Comfort Institute a training company with technical and business level membership organizations. You can contact Doc at [email protected] or call him at 800-633-7058. Go to NCI’s website at for free information, articles and downloads.

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.