Build a high-performance home for your lot
Get a home built tight and dry, so it stands up to salt air, storms and humid heat. We write its storm and air-leak targets into the drawings, then check them as the house goes up.
Send the lot address. We'll tell you the wind speed your house must be built for.
What you get with this standard.
We pursue FORTIFIED Gold on every home.
FORTIFIED is a storm standard from the Insurance Institute for Business & Home Safety (IBHS). Gold is its top tier. It covers the roof, the windows and doors, and the ties that hold the roof to the foundation. An independent evaluator checks the work before IBHS grants it. Many insurers recognize it.
We set a tight air target, then test it.
ACH50 is a measure of how leaky a house is. North Carolina's code allows up to 5 on a tested house. Our design target is under 1.0. A blower-door test, a big fan set in an outside door, checks it before you get the keys.
We plan every wall to drain and dry.
On the coast, some water always gets in. So each wall and roof gets a path for water to drain out and a way to dry. The flashing at every window and door is drawn in the order it goes on.
A tight house keeps humid air out of the walls.
Airtightness is how well a house stops air leaking through the gaps in its walls, roof and floor. Humid coastal air finds those gaps and meets a cold surface behind the drywall, where it turns to water. Drafts and damp start in the same places. So we draw one continuous air barrier before anyone frames a wall.
What a tight house does for you.
- It keeps humid air out of the walls, where it would turn to water.
- It needs a smaller heating and cooling system, which runs long enough to dry the air.
- Fresh air comes in on purpose, through a filter.
One Continuous Air Barrier
The air barrier is traced as one line across the walls, the roof and the slab. It wraps every window and door, and every pipe or wire that passes through.
Every Joint Drawn First
Airtightness depends on the joints, so we design each one before construction begins. The crew seals what the drawings show.
Tested Before Handover
North Carolina's code allows up to 5 ACH50 on a tested house. Our design target is under 1.0, written into the drawings. A blower-door test checks it before you get the keys.
How a blower-door test works
A blower door is a calibrated fan fitted into an outside doorway. It pulls air out until the house sits 50 pascals below the pressure outside. Then it measures how much air leaks back in to hold that level. Converted to air changes per hour, that is the house's ACH50.
While the fan runs, a technician can find leaks with a smoke pencil or a thermal camera. The air barrier is also inspected while it can still be seen, before the walls close.
Why air comes first
Airtightness sets the load for everything behind it. A tight house needs smaller heating and cooling equipment. It keeps humid air out of the walls. It also lets fresh air come in on purpose, through a filter. Get the air barrier right, and every other target gets easier to hit.
The joints we draw and seal
- The bottom plate, where the wall meets the floor
- The top plate, where the wall meets the ceiling and attic
- The rough opening around every window and door
- Pipes, wires and ducts that pass through a wall or ceiling
- The attic hatch
- Seams where two different assemblies meet
The barrier is only as tight as its weakest seam.
- Code ceiling
- North Carolina allows up to 5 ACH50 on a tested house.
- Our design target
- Under 1.0 ACH50.
- How it is checked
- A blower-door test before handover.
A coastal wall has to drain and dry.
Moisture management is the plan for water that gets past the outside of the house. On this coast, some water always gets in. The real question is whether the wall can drain it, dry out afterward, and still be inspected in year twelve.
Drainage Planes
A drainage plane is a layer behind the siding that sheds water down and out. Walls and windows are drawn with one, so water leaves before it does damage.
Drying Potential
Wall materials are chosen for which way they can dry, and how fast.
Dehumidification
Dehumidification means pulling moisture out of the air. On the coast, that damp is the hard problem. Temperature is the easy half.
Inspection Access
Key parts of the house stay easy to reach, check and repair for as long as you own it.
Openings and Flashing
Windows and doors are where water gets in first. The order the flashing goes on decides whether an opening drains or traps water, so we draw it.
What a moisture plan covers
Water reaches a wall three ways: as rain, as vapor moving through the wall, and as humidity in the air. A moisture plan answers all three before anyone picks a finish.
- Rain: roof runoff, splash and the grade around the house
- Vapor: how it moves through the wall
- Humidity: how much moisture the indoor air holds
- Drying: which way, and how fast, each wall can dry
- Access: whether each wall can still be inspected later
Where rot starts
Rot behind siding usually traces back to a detail somebody skipped. Flashing is the cheapest detail to get right, and among the most expensive to fix once the siding is on.
Plan for water, or repair for it later.
Planning for moisture before it appears goes further into how these walls are built.
A right-sized system keeps the air dry.
HVAC means heating, ventilation and air conditioning, the equipment that heats, cools and moves the air in a house. A tight, dry house needs less of it. Loads drop, the equipment gets smaller, and it runs long enough to pull water out of the air.
Right-Sized Loads
An oversized system short-cycles. It hits the set temperature and shuts off before it can pull out the damp. We size ours to the house we are building.
Even Distribution
Ducts and vents are laid out for quiet, even comfort in every room, including the ones far from the thermostat.
Humidity Control
On the coast, controlling the damp in the air is a design priority alongside temperature.
Planned With the Floor Plan
Mechanical needs are planned with the architecture, before the ceilings and chases close up.
Built as Drawn
The system is specified in the drawings the trade partners build from. A change on site is decided and recorded with its reason.
Why an oversized system feels clammy
Oversize the equipment and you get a failure many coastal homeowners know. The thermostat reads 72, and the house still feels clammy. The system reaches its set temperature quickly and shuts off. It never runs long enough to pull the moisture out.
How we size the system
The heating and cooling load is calculated for this house, against the envelope we are building. Sizing by rule of thumb, or by an older house down the street, overshoots a tight house. Our mechanical and building-science advisors help set the targets and plan the systems that meet them. Before the ceilings close, the drawings settle where it all goes.
- Duct paths and equipment locations
- Chases for refrigerant lines and condensate drains
- Where a dehumidifier or ventilation fan will sit
- The ceiling heights the mechanical system needs
Sizing matters even more in an accessory dwelling unit, where a small load is easy to overshoot.
Fresh air should come in on purpose.
Indoor air quality means how clean and healthy the air inside your house is. Seal a house properly, and fresh air becomes something we design. Salt, pollen and damp air arrive either way. They come through a filter and a fan sized for the house, or through whatever gaps are there.
Filtered Ventilation
Fresh air comes in through a filter we chose, at a rate calculated for your house.
Low-Emitting Materials
Finishes and adhesives that give off fewer fumes cut down avoidable pollutants inside.
Pressure Balance
A balanced system helps keep the house from pulling humid or dirty air in from places you do not want it.
Rates on the Drawings
Ventilation rates and filters are written into the drawings, so the system goes in as designed.
How ventilation works in a tight house
The tighter the house, the more the ventilation has to do on purpose. A fan brings in a measured amount of outside air, and a filter cleans it on the way in. Stale air from kitchens and baths goes back out the same controlled way. Fresh air runs on a plan we set, where a leaky house leaves it to chance.
The ventilation plan settles four things.
- How much outside air comes in, and how often
- Which filter that air passes through
- Which finishes and adhesives give off fumes
- Whether the house pulls air from places it should avoid, such as the garage
Airtightness without stuffy interiors goes deeper on the ventilation side.
The coast shapes every material we choose.
Coastal durability means building for salt air, sun, wind and upkeep from the first drawing. It shows in what holds up. Fasteners hold. Siding sheds a nor'easter and dries out behind. A roofer can still inspect the details years later without taking the wall apart.
Corrosion Resistance
Hardware, fasteners and exposed metal are chosen for salt air, and for how they hold up long after delivery day.
Rainscreen Thinking
A rainscreen leaves a small air gap behind the siding. The cladding sheds wind-driven rain, then dries out behind itself.
Coastal Wind Posture
Windows, roof shape and connections are engineered to your lot's wind exposure category.
Maintainability
You should be able to inspect, clean and repair it without a demolition crew.
Checked While Visible
Fasteners, flashing and the air barrier are inspected while they can still be seen, before the wall closes.
Why we pursue FORTIFIED Gold
FORTIFIED Gold is the storm side of durability. It looks at three parts of the house: the roof, the windows and doors, and the load path. The load path is the chain of connections that ties the roof down to the foundation. Every home we design pursues Gold, the top tier. An independent evaluator inspects the work before the Insurance Institute for Business & Home Safety (IBHS) issues it.
Your lot sets the wind design
Every lot has its own wind exposure category, set by what surrounds it: open water, open ground, trees or nearby buildings. The 2018 North Carolina Residential Code puts design wind speeds at 130 to 150 mph across the three counties. We engineer the openings, the roof and its connections to your lot's own exposure.
What we check for durability
We judge a material by how it behaves after years of salt air and hurricane seasons on this coast.
- Fasteners and hardware rated for salt air
- Siding that sheds wind-driven rain and dries out behind itself
- A wind design matched to the exposure your lot actually sees
- Access to inspect, clean and repair without tearing a wall apart
- FORTIFIED tier pursued
- Gold, the highest
- Who inspects
- An independent evaluator, before IBHS issues the designation
- Design wind speeds
- 130 to 150 mph under the 2018 NC Residential Code, depending on where the lot sits
Questions about the standard
- What is a high-performance home?
- A high-performance home is designed and built past the code minimum, for the way the coast wears on a house. Here that covers five things: airtightness, moisture management, heating and cooling, indoor air quality and coastal durability. Every home we design pursues FORTIFIED Gold and a design target under 1.0 ACH50. Both are written into the drawings and checked as the house goes up.
- What does ACH50 mean?
- ACH50 stands for air changes per hour at 50 pascals of pressure. It counts how many times an hour the air in a house is replaced while a blower door holds that pressure. A blower door is a calibrated fan fitted into an outside doorway. North Carolina's code allows up to 5 on a tested house. Our design target is under 1.0, checked by blower door before handover.
- What is FORTIFIED Gold?
- FORTIFIED is a storm standard for houses, written by the Insurance Institute for Business & Home Safety (IBHS). Gold is its highest tier. It covers the roof, the windows and doors, and the load path, the chain of connections that ties the roof to the foundation. An independent evaluator inspects the work before IBHS issues the designation. Every home we design pursues it, and many insurers recognize it.
- How do you handle moisture in a coastal house?
- We plan on some water getting in, then give it a way out. Each wall gets a drainage plane, a layer behind the siding that sheds water down and out. Wall materials are chosen for which way and how fast they dry. The flashing at every window and door is drawn in the order it goes on. Inside, the heating and cooling runs long enough to pull damp out of the air.
- Will a tight house feel stuffy?
- A tight house gets its fresh air on purpose. A fan brings in a measured amount of outside air through a filter, at a rate calculated for the house. Stale air leaves the same controlled way. Salt, pollen and damp arrive either way, and here they meet a filter first. Airtightness without stuffy interiors covers the ventilation side.
- Does this standard apply to an inland lot?
- Yes. Every home we design pursues FORTIFIED Gold and the ACH50 target, from oceanfront lots to wooded acreage inland. The 2018 North Carolina Residential Code sets design wind speeds of 130 to 150 mph in the three counties, and it marks all three warm-humid. What changes from lot to lot is the wind exposure category, set by what surrounds the house. An open inland field can carry a higher category than a wooded lot.
- Does a high-performance home cost more to build?
- Some parts do. The air barrier, the flashing details and the salt-rated hardware take more drawing and more care on site. The blower-door test and the FORTIFIED evaluation add inspections. Other parts shrink, since a tight, dry house needs a smaller heating and cooling system. We estimate cost as the design develops, so each trade-off shows up while it is still cheap to change on paper. Many insurers recognize FORTIFIED, and your agent can tell you how yours treats it.
- Do you publish measured results for finished homes?
- Tropical Tides is in its first chapter. Today we publish the standard itself: the design targets and how each one gets checked. The targets are written into every set of drawings. The tested numbers are confirmed house by house as each one is built, through its own blower-door test and FORTIFIED evaluation. Measured results join our insights as projects are completed and tested.
More on how we build.
Regulatory figures on this page summarize the town and county codes each linked city page cites, and the public sources below. Ordinances change; the parcel and the current adopted code decide, and the site analysis confirms both for your lot.
Start with your lot.
Every one of these targets is cheaper to get right on paper than on site. Tell us where you are building in Brunswick, New Hanover or Pender County. We will show you how they apply to your home.
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