Spray Foam Insulation Aquinnah MA - Quick Facts
Local energy code in Aquinnah
- Aquinnah has been an Opt-In (Specialized Code) community since January 1, 2024, layering electrification requirements on the Stretch Code; it sits in IECC Climate Zone 5A.
- Beyond the Stretch baseline, new mixed-fuel homes must be pre-wired for future electrification and add on-site solar where there is significant unshaded roof space.
- All-electric new homes must use heat pumps for space heating and hot water; fossil-fuel homes over 4,000 sq ft must reach net-zero (HERS 0), and new multifamily over 12,000 sq ft must meet Passive House.
- Aquinnah also participates in the Massachusetts Municipal Fossil Fuel-Free Building Demonstration Program - new construction and major renovations must be built fossil-fuel-free (all-electric), a step beyond the Specialized Code.
Insulation & air sealing in Aquinnah
- Spray foam is one of the fastest ways to hit the 3.0 ACH50 blower door target and the HERS 42/45 scores required in Aquinnah.
- Envelope R-values follow IECC Climate Zone 5A (roughly R-49 to R-60 attic and R-20+ walls).
- Open-cell and closed-cell assemblies are evaluated during HERS plan review; as RESNET raters, not an insulation contractor, we give unbiased guidance on where R-value and air-sealing dollars move your score most.
What you can get back: 2026 Mass Save
- Better air sealing and insulation move projects into higher Mass Save tiers - up to $25,000 for a new all-electric single-family home and up to $30,000 (Level 2) for all-electric renovations - verified by a RESNET-certified HERS rater.
RESNET-certified · 15,000+ ratings completed · 5.0 stars across 135 Google reviews · (617) 501-6788
Aquinnah, MA Spray Foam Insulation
Aquinnah sits in IECC Climate Zone 5A, so a well-insulated, air-sealed home is essential for comfort and cost. We plan and support insulation work on a mix of colonials, capes, ranches, and newer construction.
Choosing Between Open- and Closed-Cell Foam
Spray foam comes in two families, and the right choice shapes both performance and cost on a Aquinnah project.
Closed-Cell Spray Foam
Dense and rigid at roughly R-6 to R-7 per inch — the highest R-value of common insulation. It also acts as an air and vapor barrier and adds stiffness, making it ideal for rim joists, basements, crawlspaces, and roof decks in Aquinnah homes.
Open-Cell Spray Foam
Lighter and vapor-permeable at about R-3.5 to R-3.8 per inch. It expands to fill irregular cavities, seals air leaks, and dampens sound — a strong choice for interior walls and attics where drying potential matters.
A Guide to Insulation Types and R-Values
R-value measures resistance to heat flow — higher is better. Here is how the insulation materials used on Aquinnah, Aquinnah projects compare per inch of thickness.
Wood fiber
Renewable, carbon-storing batts and boards with strong sound dampening and vapor-open performance.
EPS rigid board
Expanded polystyrene; the most affordable rigid foam, used for continuous exterior and below-grade insulation.
Mineral wool (rock wool)
Dense, naturally fire-resistant and water-repellent batts or boards with excellent sound control; keeps its R-value when wet.
Closed-cell spray foam
The highest R-value of any common insulation; also acts as an air and vapor barrier and adds structural rigidity. Ideal for rim joists, basements, crawlspaces and unvented roof decks.
Fiberglass blown-in
Loose-fill for open attic floors; fast to install and settles into an even blanket over large horizontal areas.
XPS rigid board
Extruded polystyrene; moisture-resistant rigid board common under slabs and on foundation walls.
Cellulose (dense-pack)
Recycled paper fiber treated for fire and pests; dense-packs into closed wall cavities, making it ideal for retrofits.
Polyiso rigid board
The highest-R rigid foam board; foil-faced and used for continuous exterior insulation to stop thermal bridging.
Open-cell spray foam
Lighter and vapor-permeable; expands fully to fill irregular cavities, seals air leaks and dampens sound. A common choice for interior walls and vented attics.
Fiberglass batts
The most common and economical insulation; must be cut and fitted carefully because gaps and compression sharply reduce real-world performance.
MA Code Insulation Levels (Climate Zone 5)
Aquinnah falls in IECC Climate Zone 5A. New and renovated homes must meet these minimum insulation levels under the Massachusetts energy code.
| Assembly | Minimum R-value (Zone 5) |
|---|---|
| Wood-frame walls | R-20, or R-13 cavity + R-5 continuous |
| Ceilings / attics | R-49 to R-60 |
| Floors over unconditioned space | R-30 |
| Basement walls | R-15 continuous or R-19 cavity |
| Crawlspace walls | R-15 continuous or R-19 cavity |
| Slab edge (heated) | R-10, 2 ft deep |
What to Look for in a Aquinnah Insulation Contractor
Spray foam involves chemical reactions and strict safety steps, so the installer matters. In Aquinnah, look for a contractor who:
- Uses the correct foam type and thickness for each assembly to avoid off-ratio foam
- Documents R-values and provides what you need for code sign-off
- Provides a clear written scope and estimate before starting
- Licensed and fully insured for insulation work in Massachusetts
- Knows Massachusetts code, including ignition and thermal barrier requirements
- Manufacturer-certified to install specific foam systems and keep warranties valid
Insulation for Aquinnah Homes
Serving Aquinnah and the rest of Aquinnah, we tailor every insulation plan to the local building stock — a mix of colonials, capes, ranches, and newer construction — and to the demands of IECC Climate Zone 5A.
Common Spray Foam Applications in Aquinnah
Crawlspaces
Encapsulating a crawlspace with foam stops ground moisture and cold floors above.
Rim & band joists
A major air-leak point where the foundation meets framing; closed-cell foam seals and insulates it.
Exterior walls
Foam fills stud cavities completely, eliminating the gaps that reduce batt performance.
Bonus rooms & knee walls
Sealing these awkward areas fixes the hot-and-cold rooms common over garages.
Basement & foundation walls
Closed-cell foam controls moisture and adds R-value below grade.
Cathedral ceilings
Foam insulates tight roof-line assemblies where batts cannot breathe or fit well.
How a Flash-and-Fill Wall Hits Its R-Value Target
A hybrid assembly lets you buy performance only where it counts. A shallow layer of closed-cell handles air-sealing and moisture control on the cold face, while a cheaper fill carries the bulk of the thermal resistance in the rest of the cavity.
The Flash — Closed-Cell
Sprayed on the cold, outer side of the cavity, the closed-cell "flash" seals air leaks and controls vapor while the sheathing stays warm. Around two inches delivers close to R-13 by itself.
The Fill
The remaining cavity is filled with a budget-friendly material such as open-cell foam or dense-pack cellulose to complete the R-value.
Worked Example — R-30 Wall
A common recipe for a Zone 5 R-30 wall in a 2×6 cavity: about 2 inches of closed-cell (≈ R-13) against the sheathing, then roughly 4.5–5 inches of open-cell or dense-pack (≈ R-16–18), for a combined R-29 to R-31.
Because the warm, vapor-tight foam sits on the exterior side, the sheathing never gets cold enough for condensation to form. The one requirement is a closed-cell layer thick enough for Massachusetts' Zone 5 conditions.
Frequently Asked Questions
What R-value do I need in Aquinnah?
In Climate Zone 5, the code targets roughly R-20 (or R-13 + R-5 continuous) in wood-frame walls, up to R-60 in attics, and R-15 continuous on basement walls. The exact number depends on the assembly and project type.
What is the difference between open-cell and closed-cell foam?
Closed-cell foam is denser, delivers about R-6 to R-7 per inch, and acts as an air and vapor barrier — good for rim joists, basements, and roof decks. Open-cell is lighter, about R-3.5 to R-3.8 per inch, vapor-permeable, and often used in walls and attics.
What R-value do you get from 2 inches of closed-cell spray foam?
At roughly R-6.5 to R-7 per inch, two inches of closed-cell foam delivers about R-13 — and just as importantly, that layer also air-seals the cavity and provides vapor control. On many Aquinnah walls we pair that 2-inch flash with a lower-cost fill to reach the full R-value target economically.
How much insulation does an attic need?
Massachusetts code targets about R-49 to R-60 in attics. Because attics are usually the biggest source of heat loss, they are often the most cost-effective place to add insulation first.
How do you reach R-30 in a wall with spray foam?
The most cost-effective route is a hybrid, or flash-and-fill, assembly: about 2 inches of closed-cell foam (≈ R-13) against the sheathing for the air seal and vapor control, then the rest of the cavity filled with open-cell foam, dense-pack cellulose, or batt (≈ R-16 to R-18). In a standard Aquinnah 2x6 wall that combination lands right around R-30.
Can insulation be added to an existing Aquinnah home?
Yes. Dense-pack cellulose, injection foam, and spray foam can all be added to existing homes — often without major demolition — to improve comfort and efficiency.
What R-value is required for spray foam in Massachusetts?
Massachusetts sits in Climate Zone 5. Above-grade walls generally need about R-20 (or R-13 cavity plus R-5 continuous), attics roughly R-49 to R-60, floors over unconditioned space about R-30, and basement or crawlspace walls around R-15 continuous. We size the foam on every Aquinnah project to the value your assembly needs to pass code.
Does Mass Save cover spray foam insulation?
Mass Save is a real Massachusetts efficiency program that Aquinnah homeowners can explore. It typically funds a no-cost home energy assessment and offers incentives toward weatherization and air sealing; coverage for spray foam specifically can vary and often depends on the assessment, so we help you understand what your project may qualify for.
HERS Ratings Across Aquinnah and Nearby Communities
Home Energy Efficiency Consultants rates new homes, additions, and major renovations throughout Aquinnah — including Aquinnah Center, and Gay Head. Every Aquinnah project is filed with the Town of Aquinnah Building Department, and we handle the energy model, blower door and duct leakage testing, and the compliance paperwork from start to finish.
We also serve the communities right around Aquinnah, including Chilmark, West Tisbury, and Edgartown. Our Framingham office at 68 South St is the closest of our four Massachusetts locations — see our Framingham office or call (617) 501-6788 to get a Aquinnah rating on the schedule.
Aquinnah Specialized Energy Code — HERS Index Targets
Aquinnah enforces the Massachusetts Specialized (Opt-In) Energy Code. The required HERS score depends on fuel type and project scope — a lower index is stricter. As a fossil-fuel-free community, new construction in Aquinnah must be built all-electric, so the all-electric columns apply.
| Project type | Mixed-fuel | Mixed-fuel + solar | All-electric | All-electric + solar |
|---|---|---|---|---|
| New construction | HERS 42 | 42 | 45 | 45 |
| New construction — embodied-carbon credit | 45 | 45 | 48 | 48 |
| Accessory dwelling unit (ADU) | 52 | 55 | 55 | 58 |
| Major alteration / renovation / change of use | 65 | 70 | 70 | 75 |
A HERS rating is triggered by new construction, additions over 1,000 sq ft (or more than 100% of the existing conditioned area), and Level 3 alterations over 1,000 sq ft affecting more than 50% of the home. New homes must also pass a blower-door test at 3.0 ACH50 and include electrification-ready wiring for heat pumps, EV charging, and solar. We model your Aquinnah project up front so you know the exact target and the fastest path to hit it — call (617) 501-6788.
