Build a custom new home for your lot

Your lot settles three things first.

• Your flood zone sets how high the house sits, and local rules add one to three feet more.
• Your wind speed is 130, 140 or 150 mph, set by where the lot sits.
• Inland, the soil test for a septic system can decide where the house goes.

Oceanfront

On the ocean strand, a lot often sits in Zone VE, the wave zone on the flood map. There the code measures height to the bottom of the lowest horizontal structural member, the lowest beam under the floor. It also bars fill dirt as structural support. The state's oceanfront setback under CAMA, the Coastal Area Management Act, marks how close to the ocean the house can sit. It is measured from the first line of stable natural vegetation, then scaled to the erosion rate and the size of the house. For a house under 5,000 square feet, it starts at 60 feet. Towns add their own lines. Carolina Beach keeps an oceanfront Development Line of its own, and Kure Beach caps every building at 35 feet. Freeboard is the extra height a town's flood rule adds above the mapped flood height. On the strand, it runs from one foot on Oak Island to three feet at Topsail Beach.

Canal

A canal lot often trades the wave zone for an AE zone. There, outside a Coastal A Zone, height is measured to the top of the lowest floor. A canal lot also brings a bulkhead, a dock and a rear setback, and CAMA can push that setback past the town's zoning table. On Oak Island, an oceanfront lot, a Davis Canal lot and an inland lot a few blocks apart can carry three different flood zones. Ocean Isle Beach sorts its new construction into three kinds of lot: canal, oceanfront and mainland.

Marsh and sound

Along the sounds and the Intracoastal Waterway, the marsh draws the line. The state protects the estuarine shoreline as an Area of Environmental Concern, a strip that runs 75 feet landward of normal high water. New building inside it generally sits 30 feet back from the water. In Masonboro, salt marsh on a house lot carries the strictest conservation-space setback in New Hanover County's table: 100 feet, plus a 35-foot vegetated buffer. A Hampstead site analysis often finds less buildable ground than the plat implies. In Scotts Hill, the first question is which county the lot sits in.

Inside the gates

A lot in a planned community answers to two sets of rules: the association's architectural review and the government's permit. In St. James, the design-review committee sees the house first. Then comes the town's zoning and floodplain review, and then Brunswick County issues the building permit. In Leland, each master-planned community runs an architectural review that the town neither administers nor can waive. On the mainland side of Sunset Beach, a golf-community lot leaves the island's CAMA and flood questions behind. It brings a high water table, pond drainage and HOA review instead.

In-town grid

An infill lot in an older grid comes with neighbors close by, utilities at the street and, in some towns, a historic district. In Southport, exterior work in the local historic district needs a certificate of appropriateness from the Historic Preservation Commission before a building permit. That includes new houses. Southport's tree ordinance also protects its heritage live oaks. In Wilmington, a lot zoned R-5 or R-3 can set its front and rear setbacks within five feet of the block's average. In Burgaw, most grid lots already have a tap at the street on the town's own water and sewer.

Wooded acreage on a well and septic

Inland, the soil sets the plan. On a Castle Hayne tract, the county's septic evaluation, which tests the soil and the site, fixes where the septic system can go. That, in turn, fixes where the house can go. Around Maple Hill, the soil survey leads the analysis. Ground that reads as simple acreage on a listing can hold wet soils. Those may need a wetland delineation, a survey that maps the wetland's edge, before anyone can call them buildable. A Currie tract often holds dry ridge and wet swamp bottom side by side. In Winnabow, septic capacity usually decides how many houses a parcel can carry. On Rocky Point family land, an old farm lane has to meet the county's access-easement standard before a new house can be permitted.

Two of those facts change more from town to town than most people expect. The first is freeboard, the extra height a local flood ordinance adds above the base flood elevation (the flood height FEMA's map sets). It runs from one foot in Oak Island and Kure Beach to three feet in Southport, Ocean Isle Beach and Topsail Beach. Most other places use two feet. In a VE zone, the code measures that height to the bottom of the lowest horizontal structural member, the lowest beam under the floor. In an AE zone outside a Coastal A Zone, it measures to the top of the lowest floor.

The second is design wind speed, the gust speed the code says a house must be built to withstand. It follows lines on a map. In Brunswick and New Hanover Counties, the line is US 17: 140 mph to the west and 150 mph to the east. That puts Leland, Shallotte and Winnabow on both sides of it. Pender County draws its lines by township and waterway instead: 150 mph east of the Intracoastal Waterway and 140 mph in mainland Topsail Township. The rest of the county, including Burgaw, is 130 mph. A 150 mph lot also brings in Chapter 46 of the state code, the coastal construction standards for piling, fasteners, anchorage and roof tie-down.

Wind speed is one input to the load. The exposure category, set by what surrounds the lot, can raise it. Open farmland around Atkinson can push a 130 mph site toward the loads a sheltered subdivision sees at 150 mph. A lot can also touch an Area of Environmental Concern, a stretch of shoreline the state protects. There the Coastal Area Management Act (CAMA) adds its own permit and setbacks. Inland, the soil evaluation for a septic system can decide where the house sits before design starts.

Freeboard above base flood

One foot in Oak Island and Kure Beach. Three feet in Southport, Ocean Isle Beach and Topsail Beach. Two feet in most other towns, and in the unincorporated parts of all three counties.

Design wind speed

130 mph in inland Pender County. 150 mph on the islands, and east of US 17 in Brunswick and New Hanover.

CAMA review

Any lot inside an Area of Environmental Concern: the ocean hazard area, estuarine shorelines, public trust shorelines.

Water and wastewater

Public water and sewer in towns such as Southport, Oak Island, Carolina Beach and Burgaw. A well and septic system serve much of the inland acreage.

CAMA sits alongside all four. Any lot inside an Area of Environmental Concern generally needs a CAMA permit as well. Minor permits usually come from a local permit officer. Sunset Beach routes them instead to the state's Division of Coastal Management, which also decides every major permit.

Every home we design pursues FORTIFIED Gold. Gold is the top tier of a standard the Insurance Institute for Business & Home Safety (IBHS) writes. A credentialed evaluator inspects the work before IBHS issues the designation, and many insurers recognize it. Airtightness gets the same treatment. A design target under 1.0 ACH50 (a measure of air leakage) is written into the drawings and carried into construction. A blower-door test checks it before handover. How a tight house still breathes covers the ventilation that goes with it.

Tropical Tides holds NC Residential Contractor License #109520 and belongs to the Brunswick County Home Builders Association. How the trade partnerships are set up and supervised is on the approach page. Southport is our home base, and you can reach us at 910-946-5512.

Most of the anxiety in building a custom home comes from not knowing. What was decided? What did it cost? What happens next? Did the thing you asked for three months ago survive?

Your private client workspace holds the project documents, from the site analysis to the current drawing set. It also holds each decision with the reasoning behind it, your selections and the build schedule. A client who can see the project can ask better questions and decide faster.

Calm comes from knowing where things stand.