East Central: energy calcs & Manual J.
Daytona’s design data on the coast, Sanford’s inland.
Volusia and Flagler share Daytona Beach International's design limits, 91°F cooling and 39°F heating, while Seminole uses Sanford's 93°F and 38°F. All three counties are climate zone 2A. Flagler is the newest housing market of the three, with 58.2% of homes built since 2000; Volusia's median home dates from 1986.
- Counties
- 3 countiesVolusia, Flagler and Seminole
- Departments
- Each county’s ownSeveral cities run their own · what we publish
- Code edition
- FBC Energy Conservation, 8th Ed. (2023)9th Ed. (2026) scheduled for Dec 31, 2026 · what changes
- Price
- $195 · $445 · $595Energy calc from · full package · sealed. Same in all 67 counties · price list
- Ready by
- 2–3 business daysExpedited: within 24 business hours, +$150. Clock starts when complete plans pass intake (3:00 PM ET cutoff) · how it works
Volusia, Flagler and Seminole
Per-county table3 counties · zone, design °F, permits, housing
| County · stations | Zone | Design °F | Permits | Median built | Single-family | Mobile | Electric heat |
|---|---|---|---|---|---|---|---|
| VolusiaDaytona Beach International Airport (Manual J) | 2A | 91° / 39° | 2,079 #20 | 1986 | 64.5% | 8.0% | 92.9% |
| FlaglerDaytona Beach International Airport (Manual J) | 2A | 91° / 39° | 1,950 #21 | 2002 | 79.6% | 3.6% | 93.5% |
| SeminoleSanford (Manual J) | 2A | 93° / 38° | 893 #31 | 1988 | 61.4% | 2.1% | 92.3% |
What it means for sizing
2 paragraphs · design temperatures, housing stock, equipment
Two degrees of cooling design separate Seminole from the coast: Sanford's 93°F against Daytona Beach's 91°F, with heating limits a degree apart at 38°F and 39°F.2 All three are zone 2A.1 On a two-storey Seminole house with west glass, our experience is that those two degrees and the orientation together can move a selection by half a ton; the Manual J has to show it.
Flagler issued 1,950 one-unit permits in 2025 and Volusia 2,079, while Seminole, mostly built out, issued 893.3 Flagler's housing is overwhelmingly single-family detached, 79.6%, with only 8.3% built before 1980.4 Seminole has the lowest owner-occupancy here at 66.2%.4
Worked example
2,500 sq ft house in Seminole County → 29,820 Btu/h, 2.48 tons · illustrative
Illustrative · not a Manual J
A 2,500 sq ft two-storey frame house at Seminole's 93°F limit, the hottest in this group.2 The 4.5 ACH50 and frame walls are assumptions, not a survey of local practice.
| House | new two-storey frame home, Sanford area |
|---|---|
| Conditioned area | 2,500 sq ft, 2 storeys, 9 ft ceilings |
| Bedrooms / occupants | 4 / 5 |
| Glazing | 15% of floor area (375 sq ft), U 0.3, SHGC 0.25 |
| Walls / ceiling | R-13 walls, R-38 ceiling under a vented attic |
| Air leakage | 4.5 ACH50 |
| Ducts | in the attic, 7% gain allowance |
| Outdoor design | 93°F cooling / 38°F heating (Seminole County, sourced) |
| Indoor design | 75°F cooling / 70°F heating |
| Design grains difference | 45 gr/lb (assumption) |
Illustrative only. A simplified block-load estimate with the inputs shown, not an ACCA Manual J, and not for permitting. A real calc goes room by room with your plans, orientation and equipment data.
Building departments
How we publish department checklists
Every county here has its own building department, and several cities run their own. We publish a department's checklist, contacts and quirks only after reading them on its official page, and each county here gets its own page once that's done. Until then, check with the county building department before you submit. Ordering works statewide today.
East Central questions
3 answers · What design temperatures apply in Daytona Beach and Palm Coast?
What design temperatures apply in Daytona Beach and Palm Coast?
Volusia and Flagler counties both use Daytona Beach International Airport's limits: 91°F at 1% cooling and 39°F at 99% heating. That's RESNET's county table, drawn from Manual J design data. A Manual J for a Palm Coast or Daytona house should not exceed those outdoor conditions.
Is Seminole County's cooling design hotter than the coast?
Yes, by two degrees. Seminole takes Sanford's 93°F cooling limit, while Volusia and Flagler use Daytona Beach's 91°F. Heating is close: 38°F in Seminole and 39°F on the coast. On large west-facing glass, those two degrees can change the equipment size, so run the actual orientation.
How busy is new home permitting in Flagler County?
Flagler issued 1,950 permits for new single-family units in 2025, according to the Census Bureau's Building Permits Survey, ranking 21st of Florida's 67 counties. Volusia issued 2,079. We deliver in 2–3 business days once intake passes, which matters most when a builder is filing several models at once.
Nearby and related
Price
One statewide price in all 67 counties. Building departments decide what they accept; we don’t guarantee approval. Revisions for plan-review comments on the same design are free.
Sources
4 primary references · numbered to match the citations
- 012023 Florida Building Code, Energy Conservation (8th Ed.), Table R301.1, climate zones by countyup.codes
- 02RESNET / ENERGY STAR, Appendix A: HVAC Design Temperature Limits by State and County (v4, 2019)resnet.us
- 03U.S. Census Bureau, Building Permits Survey, 2025 annual county data (new privately-owned 1-unit housing units)www2.census.gov
- 04U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates (B25001, B25003, B25018, B25024, B25034, B25035, B25040), via Census Reportercensusreporter.org