60 Rockland Drive Net Zero Build
60 Rockland Drive is a custom net-zero single-family home in coastal Rhode Island, designed and built by NJ&J Builders and submitted under the U.S. Department of Energy Zero Energy Ready Home (ZERH V2 Rev 1) Renewable Equipped path. The project pairs a high-R, low-leakage envelope with a single 2.5-ton variable-capacity cold-climate heat pump and a balanced ERV — all sized and field-commissioned with full ACCA Manual J / S / D documentation, ANSI/RESNET/ACCA Standard 310 compliance, and ENERGY STAR Cold Climate sizing justification.
What makes this build distinctive is not exotic equipment — variable-capacity cold-climate heat pumps with heat-pump water heaters and ERVs are increasingly the default for Net Zero work in Climate Zone 5A. What's distinctive is the rigor of the engineering documentation: a Manual S addendum the rater needs to see rather than the one software auto-generates, ventilation certified at the speed and zone it actually runs at, and three Performance-Path tradeoffs disclosed up front rather than buried in the load calc — a conditioned-but-unfurnished walkout basement modeled inside the certified envelope, a one-door UA tradeoff for an architectural Solid Wood door, and a walkout-constrained AED excursion applied as a 1,142 Btuh penalty to the basement cooling load.
The home is all-electric — no fossil fuel appliances anywhere — and is currently progressing toward substantial completion. HERS Index is pending REM/Rate scoring by CLEAResult; final PV array specifications and finished photography will be added once the rater signs the ZERH V2 Rev 1 National Rater Checklist.
- DOE Zero Energy Ready Home (ZERH V2 Rev 1) — Performance Path
- All-electric: no fossil fuels anywhere in the home
- Mitsubishi 2.5-ton variable-capacity cold-climate heat pump (ENERGY STAR Most Efficient)
- Rheem 50-gallon heat pump water heater (3.88 EF)
- Zehnder ComfoAir Q-450 ERV — 85% sensible / 70% latent recovery
- EPA Indoor airPLUS V1 Rev 04 — low-VOC paint, MERV-8 filtration, balanced ventilation
- EPA WaterSense Path 5.2 — Kohler Santa Rosa toilets and Purist faucets/showerheads
- 100% LED lighting, ENERGY STAR Café and LG appliances
- EV-Ready: 208/240V 30A garage receptacle on dedicated labeled breaker
- Renewable Equipped — on-site PV array sized to ZERH requirement
Engineering Performance
Measured Performance & System Specs
- HERS Index
- Pending CLEAResult REM/Rate (target ≪ 50; ZERH HERS target materially below baseline ENERGY STAR SFNH V3.2)
- Air Tightness
- 1.4 ACH50 @ 50 Pa whole-envelope blower door (ZERH limit ≤ 3.0)
- Heating Load (Manual J)
- 30,025 Btuh @ 7°F outdoor / 70°F indoor (ACCA Manual J 8th Ed.)
- Cooling Load (Manual J)
- ≈18,584 Btuh @ 87°F / 75°F / 50% RH
- Conditioned Floor Area
- 4,015 ft² (1,963 ft² 1F + 2,052 ft² walkout basement, modeled inside certified envelope)
- Climate Zone
- IECC 5A · Coastal Rhode Island
- HVAC System
- Mitsubishi SUZ-AK30NLHZ + SVZ-AP30NL 2.5-ton variable-speed cold-climate heat pump · AHRI 215712240 · ENERGY STAR Cold Climate / Most Efficient · all ducts and AHU inside conditioned envelope (zero duct-loss penalty)
- Ventilation
- Zehnder ComfoAir Q-450-ERV — 85% sensible / 70% latent recovery · field-commissioned 4/18/2026 · 103 CFM supply / 106 CFM exhaust at medium continuous · ASHRAE 62.2-2010 compliance with +46 CFM margin (~80% above floor)
- Domestic Hot Water
- Rheem PERFORMANCE PLATINUM XE50T10HS45U1 — 50 gal heat pump water heater · 3.88 EF · AHRI 207094237
Envelope
- Above-grade walls2×6 advanced framing + continuous insulation — U-0.040 / R-28.4
- Basement walls (full height)Cavity + ci, walkout configuration — U-0.058 / R-18.7
- Slab21B-24t with R-10 perimeter foam to 24″ depth
- Ceiling — flatU-0.022–0.024 / R-49
- Ceiling — vaulted (1,461 ft²)U-0.022 / R-49
- WindowsAlpen CW 625 Series + Narrow Line slider — U-0.16–0.19
- Net envelope UA32–36 Btuh/°F BELOW ZERH prescriptive reference (~20× margin over the one Performance-Path door tradeoff)
Compliance & Certifications
- U.S. DOE Zero Energy Ready Home V2 Rev 1 — Performance Compliance Path
- ENERGY STAR SFNH V3.2 baseline (Cold Climate sizing per Item 4.15 PASS)
- EPA Indoor airPLUS V1 Rev 04
- EPA WaterSense Path 5.2
- Renewable Equipped — PV array installed
Outcomes
What This Build Delivered
- 1.4 ACH50 air-tightness — half the ZERH ceiling, less than half a typical new-construction baseline
- Manual S Approach 4 PASS on every concurrent sizing pathway (113% heating · 141% cooling per Std. 310 · 159% whole-house cooling cleared via Cold Climate exemption)
- Net envelope UA approximately 32–36 Btuh/°F below the ZERH reference home — a ~20× headroom margin over the single Performance-Path door tradeoff
- All-electric mechanical system with on-site PV — no combustion, no fossil-fuel infrastructure
“The differentiator on this project isn't equipment selection — variable-capacity cold-climate heat pumps with HPWHs and ERVs are increasingly the default for Net Zero work in CZ 5A. The differentiator is whether the engineering documentation can take you from permit through HERS rating without rework. The submittal is the product, as much as the building is.”
Photos and full case study coming soon
We're finishing this build now and preparing the full case study, including energy modeling, HERS rating, and finished photography. Check back soon, or get in touch to discuss a Net Zero build for your home.
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