Crawl Space Insulation
Crawl spaces are a major source of moisture, drafts, and energy loss in South Florida homes. Cardinal seals crawl spaces with closed-cell spray foam — a moisture barrier, air barrier, and insulator in one — that stops ground moisture, eliminates floor drafts, and protects against mold and wood rot.
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ProPink fiberglass, installed to manufacturer spec
Before-and-after infrared proof on every job
Local crews, never subcontracted
Transferable to the next owner
Crawl Space Insulation for South Florida Properties
crawl space insulation is the workhorse of Florida attic retrofits. We will tell you plainly when it is the right specification and when a less expensive approach delivers the same outcome.
South Florida sits in South Florida, where the recommended attic target is R-38 to R-49. That number, along with where your ductwork runs and what condition the existing assembly is in, is what determines the right specification for your property.
Crawl Space Insulation at a glance
- R-value
- R-6.5 / inch (closed-cell spray foam)
- Installed cost
- $2.50 – $7.00 per sq ft installed
- Service life
- 80+ years (closed-cell foam)
- Available in
- South Florida and throughout South Florida
Types and Methods
Closed-cell foam encapsulation
Closed-cell spray foam applied to the crawl space walls and ground (or vapor barrier). It acts as insulation, vapor barrier, and air seal in one application — stopping ground moisture, eliminating floor drafts, and conditioning the space. This is our standard for South Florida crawl spaces.
Floor joist insulation
Fiberglass batts or closed-cell foam installed between the floor joists above the crawl space. Less comprehensive than encapsulation but useful where budget or access is limited. We pair it with a ground vapor barrier for moisture control.
Crawl space insulation requires addressing any active water intrusion first. If we find standing water, plumbing leaks, or drainage problems, those get corrected before any insulation goes in — otherwise the insulation traps the moisture and accelerates mold and rot.
Benefits for South Florida Property Owners
- Stops ground moisture migration that causes mold and rot.
- Eliminates cold-floor drafts and uneven temperatures.
- Closed-cell foam = insulation + vapor barrier + air seal in one.
- Protects subfloor structural integrity from humidity damage.
- Reduces musty odors and improves indoor air quality.
Best Applications
- Homes with cold floors and drafty living spaces
- Crawl spaces with visible moisture or mold
- Homes with musty odors and high indoor humidity
- Older homes with uninsulated floor joists
- Properties where ductwork runs through the crawl space
How We Install It
- 1Inspect the crawl space for moisture, mold, and structural issues
- 2Remove debris and address any active water intrusion first
- 3Install a ground vapor barrier if not already present
- 4Spray closed-cell foam to the walls and/or floor joists to specified depth
- 5Seal all penetrations — plumbing, wiring, and HVAC ducts
- 6Verify the space is conditioned and moisture is controlled
- 7Document the work with before-and-after photos
Cost and R-Value Reference
Florida insulation cost & R-value reference.
Typical installed costs across South Florida by material. Pricing varies with access, square footage, and site conditions — every Cardinal quote itemizes material, R-value, installed inches, and square footage.
| Material | Installed cost | R-value / inch | Service life |
|---|---|---|---|
| Blown-in fiberglass | $1.10 – $2.00 / sq ft | R-2.2 – R-2.7 / in | 20–30 years |
| Blown-in cellulose | $1.20 – $2.40 / sq ft | R-3.2 – R-3.8 / in | 20–30 years |
| Fiberglass batts | $0.90 – $2.10 / sq ft | R-3.1 – R-3.4 / in | 25+ years |
| Mineral wool | $1.60 – $3.40 / sq ft | R-3.0 – R-4.3 / in | 50+ years |
| Open-cell spray foam | $1.50 – $3.20 / sq ft | R-3.6 – R-3.8 / in | 80+ years |
| Closed-cell spray foam | $2.40 – $4.90 / sq ft | R-6.0 – R-7.0 / in | 80+ years |
| Rigid foam board | $1.40 – $3.80 / sq ft | R-3.8 – R-6.5 / in | 50+ years |
| Radiant barrier | $0.55 – $1.90 / sq ft | Reflective (no R) | 25+ years |
| Duct sealing + R-8 wrap | $800 – $3,500 / system | R-8 (duct) | 15–25 years |
| Insulation removal | $1.10 – $2.90 / sq ft | — | One-time |
Pricing reflects typical Florida installed costs and varies with access, square footage, and site conditions. Source: U.S. Department of Energy insulation guidance, Florida Building Code R402, and IECC climate zone 1 requirements.
Pricing reflects typical Florida installed costs and varies with access, square footage and site conditions.
Crawl Space Insulation FAQs
Closed-cell spray foam crawl space insulation typically runs $2,500–$7,000 depending on square footage and access. It doubles as encapsulation — moisture barrier, air seal, and insulation in one application.
In South Florida's humid climate, sealing the crawl space walls and ground (encapsulation) with closed-cell foam outperforms insulating the floor joists. It conditions the space and stops moisture at its source.
Dramatically. Closed-cell foam is a Class II vapor retarder — it blocks ground moisture migration that drives indoor humidity, musty odors, and mold. Most homeowners notice the difference within days.
Serving the Boca–Delray–Boynton corridor.
From the Boca inlet to Boynton's western estates — every hot zone below is a home we sealed this year. This is our local service area.











