A West Chester whole-home foam package with energy-recovery ventilator pairing

The starting point

A 2007 home in West Chester, 2,950 sqft, full unfinished basement, attached two-car garage. Built with code-minimum fiberglass batts in walls (R-13), R-30 attic, R-19 in the floor over the unfinished basement. Pre-foam blower-door test: 7.8 ACH50, typical for code-minimum 2007 construction.

The owners wanted a whole-home foam upgrade as a comfort + utility-cost improvement. They were not in a hurry; they wanted the work scoped properly and were open to multi-day install.

Why ventilation pairing matters at this tightness target

Whole-home foam packages routinely bring blower-door measurements down to 3-5 ACH50, which is excellent for thermal performance but borderline for natural ventilation. ASHRAE 62.2 recommends 0.35 air changes per hour minimum continuous fresh-air ventilation for indoor air quality. At 3-5 ACH50, the natural infiltration during normal weather averages around 0.15-0.30 ACH continuous, below the IAQ minimum.

Without mechanical ventilation, tight homes show predictable problems:

• Elevated indoor humidity (cooking, showering, breathing accumulate moisture)
• Stale-air sensation in winter (when occupants close windows for weeks)
• Elevated CO2 in occupied rooms (particularly bedrooms overnight)
• Persistent cooking odors that take longer to clear
• Potential mold growth on cool surfaces
• For homes with natural-draft gas furnaces or water heaters: back-drafting risk on a depressurized envelope (the combustion appliance pulls air down its own flue, spilling combustion gases into the home). Tight homes with combustion appliances should pair the foam install with a combustion-safety test and a radon retest within 90 days because both checks measure the same air-pressure dynamics from different angles.

The fix: an energy-recovery ventilator (ERV) sized to the home, providing controlled fresh-air introduction with energy recovery from the exhaust air. Cincinnati climate generally favors ERV over HRV because of summer humidity loads (the moisture-recovery feature reduces latent cooling load on the AC).

The combined quote

| Foam scope | Cost | |---|---| | Closed-cell rim joist (2 inches) | $2,400 | | Closed-cell at attic roof deck (4 inches) | $7,500 | | Wall cavity drill-and-fill closed-cell | $5,800 | | Closed-cell at unfinished basement walls | $2,800 | | Pre/post blower-door tests | $400 | | Closeout package (R-value cert, product data, ICC-ES) | $200 | | Foam subtotal | $19,100 |

| ERV scope | Cost | |---|---| | Panasonic FV-04VE1 ERV (rated 60 CFM continuous) | $1,200 | | Ductwork, dampers, controllers | $1,400 | | Installation labor (1 day) | $850 | | Wall-mounted controller + balancing | $250 | | ERV subtotal | $3,700 |

Combined total: $22,800 fixed.

Install timeline (6 days)

• Days 1-2: Foam install (rim joist + basement walls Day 1, attic roof deck Day 2)
• Day 3: Wall drill-and-fill begins
• Day 4: Wall drill-and-fill complete + patch + paint
• Day 5: Blower-door post-test (4.4 ACH50, down from 7.8) + ERV install
• Day 6: ERV balancing + verification

The 12-month follow-up

| Metric | Pre-install | Post-install | |---|---|---| | ACH50 (blower door) | 7.8 | 4.4 | | Indoor RH winter average | 22% (too dry) | 38% (comfortable) | | Indoor RH summer average | 64% (humid) | 51% (comfortable) | | Annual heating cost (Nov-Mar) | $1,540 | $920 (-40%) | | Annual cooling cost (Apr-Oct) | $920 | $640 (-30%) | | Total annual utility savings | n/a | $900/year |

The 30-40% utility cost reduction is at the upper end of typical West Chester post-foam outcomes. The humidity stabilization (winter dryness fixed; summer humidity manageable without running AC continuously) was the most-valued non-financial benefit reported.

What this case shows for whole-home foam upgraders

If you are scoping a whole-home foam package on a 2000-2010 West Chester, Mason, Liberty Township, or Loveland home, plan for the ERV/HRV pairing:

1. If the post-install blower-door test will land at 4.5 ACH50 or below, plan for ventilation upgrade. 2. If the post-install ACH50 will land between 4.5-6.0, ventilation upgrade is borderline. 3. If the post-install ACH50 will be above 6.0, ventilation upgrade is generally not required.

Bundle the ERV with the foam at quote time. It adds $2,800-$5,500 to the total but avoids retrofitting later when air-quality concerns surface.