Written by Eric Gans
I have completed over 2000 Home Performance with ENERGY STAR® home energy audits in Maryland, and I like to write about my experiences.
Laurie contacted me because she was planning to replace the HVAC system in her 43-year-old home.
She had already spoken with several HVAC contractors and noticed something strange:
The proposals varied dramatically in price, but nobody was asking why certain rooms were uncomfortable.
One upstairs bedroom was consistently too hot in summer and too cold in winter.
Several rooms felt drafty.
She could feel air around outlets and switches.
And despite talking to multiple HVAC companies, nobody mentioned Maryland's EmPower rebate program.
That led her to schedule a Home Performance Energy Audit.
Shiny and new, but the air coming out is the same?
What Most Homeowners Assume
Most people assume comfort problems are caused by:
- An old HVAC system
- Not enough airflow
- Bad thermostat settings
- The need for zoning
- The need for mini-splits
Sometimes that's true.
But often the HVAC system tries to compensate for problems caused by the building envelope.
Think of it this way:
A bigger furnace doesn't fix an open window.
A more expensive heat pump doesn't stop air leakage.
A zoning system doesn't add insulation.
What We Found
When we evaluated the home, we found something interesting.
The attic already had a reasonable amount of insulation for its age.
The bigger problem was air leakage.
Numerous openings throughout the attic floor were allowing conditioned air to escape:
- Electrical penetrations
- Plumbing penetrations
- Recessed lighting
- Top plate connections
- Attic access hatch
At the same time, the basement rim joists were allowing outdoor air to enter the home.
The house was essentially leaking air from both the top and bottom.
This is extremely common in homes built during the 1980s.
Why The HVAC System Wasn't The First Problem To Solve
Laurie had been considering:
- HVAC replacement
- Zoning
- Mini-splits
Those solutions may have helped.
But they would have been treating symptoms rather than causes.
Before spending money on more equipment, it made sense to improve the building envelope.
That meant:
Attic Air Sealing
Seal the hidden openings in the attic floor.
Attic Insulation Upgrade
Bring insulation levels closer to modern standards.
Rim Joist Sealing
Stop outdoor air from entering through the basement perimeter.
Mechanical Ventilation
Provide controlled fresh air after tightening the house.
The Result
The improvements were completed by late March.
By May, Laurie received a rebate check for:
$9,678.76
More than $6,000 of that came from the HVAC replacement she was already planning to complete.
The remainder helped offset the cost of air sealing and insulation improvements.
But the rebate wasn't the biggest win.
According to Laurie:
- The house is more comfortable
- The air quality improved
- The uncomfortable rooms perform better
- She gained a better understanding of how her house works
Check out the Google Review here.
What Homeowners Can Learn From This
If you're considering HVAC replacement, ask yourself:
- Why is the room uncomfortable?
- Where is the house leaking air?
- Is the attic properly air-sealed?
- Are the rim joists sealed?
- Is insulation performing as intended?
- Are there rebate opportunities being overlooked?
A new HVAC system may absolutely be part of the solution.
But before replacing equipment, it's worth understanding whether the house itself is causing the problem.
The most expensive HVAC system in the world still has to fight an inefficient building envelope.
Final Thought
Laurie's experience highlights something I see regularly during energy audits.
Many homeowners begin the process thinking they need a new HVAC system.
What they actually need is a better understanding of how their home works.
Sometimes that leads to new equipment.
Sometimes it doesn't.
Either way, the goal is the same:
Find the root cause first.
Then spend money where it will have the greatest impact.
