Measured against the Florida code
The attic numbers, not a brochure
The 2023 Florida Building Code, Energy Conservation, Table R402.1.2 sets a climate zone 1 ceiling at R-30 and a climate zone 2 ceiling at R-38. Cardinal installs R-38 and checks the inches. A Florida page that lists R-49 to R-60, or R-3.2 to R-3.8 per inch for both fiberglass and cellulose, is using a different book. Table R402.4.1.1 says air-permeable insulation shall not be used as the air seal.
Quotes are prepared by Russell Y, a building scientist, BPI certified, and certified to perform blower door testing. When the door is run, the result is air changes per hour at 50 pascals, the method in R402.4.1.2. That section limits new houses in climate zones 1 and 2 to 7 ACH50. An insulation job on an existing house is not automatically that test. We report the number only when we measured it.
Insulation numbers Cardinal uses against the Florida code| Item | Number | What it means |
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| Zone 1 ceiling, Florida code | R-30 minimum | Palm Beach and Broward |
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| Zone 2 ceiling, Florida code | R-38 minimum | Not R-49 and not R-60 |
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| What Cardinal installs | R-38, depth checked | Above the zone 1 floor |
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| New blown fiberglass | About R-2.5 per inch | Not R-3.2 to R-3.8 |
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| Settled fiberglass | About R-2.2 per inch | 4 inches is about R-9 |
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| New cellulose | About R-3.6 per inch | Denser. Still not an air seal |
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| Open-cell foam | About R-3.6 per inch | A roof-deck product |
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| Closed-cell foam | About R-6.5 per inch | 2 inches is about R-13 |
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The attics on this page
West Boca is not a city and it does not have a street address. 33496 is the club side off Yamato and Glades, west of Jog: Woodfield Country Club and The Hamptons, mostly one story under tile, original batts slumped to something near R-9. The Hamptons gate is inside the club. The crew does not have a code.
33428 is west of State Road 7. Sandalfoot Cove is early-1970s ranches and a garage hatch that is also a large hole. Boca Falls sits between Glades and Palmetto Park, two gates, about 722 houses. 33498 is farther west, including parts of Mission Bay at Glades and State Road 7. Ten sections there means one attic does not describe the next.
A near-me search from any of these ZIPs starts miles from 4263 NW 1st Ave. The R-38 number does not change because of the drive. Condos with no scuttle are not this job. The pin stays at the Boca shop.
The code in West Boca Raton
West Boca Raton is in Palm Beach County. Table R301.1 of the 2023 Florida Building Code, Energy Conservation, lists Palm Beach County as climate zone 1A. Table R402.1.2 sets the zone 1 ceiling minimum at R-30. West Boca Raton does not publish its own attic R-value. The city enforces the Florida Building Code.
Palm Beach County is not in the High-Velocity Hurricane Zone. That zone is only Miami-Dade and Broward. Parts of the Palm Beach coast are still a wind-borne debris region, which is an opening-protection rule from the wind map, not an insulation number. Section R806.2 of the 2023 Florida Building Code, Residential, sets the net free vent area at 1/150 of the attic. The exception is 1/300 only when 40 to 50 percent of that area is within 3 feet of the ridge and the rest is in the bottom third. Insulation cannot close the soffit. R806.3 requires at least 1 inch at the eave vent.
The county zone is Table R301.1. The Boca Raton worked example, including the vent math, is the building code page. Cardinal still installs a vented attic to R-38 and checks the depth.
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