Custom Homes Deserve Custom HVAC
Sunset is a community where new construction often means a custom home on a family lot rather than a cookie-cutter subdivision build. That individuality is exactly why the HVAC system shouldn’t be treated as an afterthought. A custom floor plan, whether it’s 1,400 square feet or 3,500, needs an HVAC design that matches its specific layout, insulation package, and the demands of St. Landry Parish’s long, humid cooling season.
F & R Air Conditioning brings the same engineering rigor to a new home in Sunset that we apply to projects across Acadiana. The process doesn’t change based on community size. Your home gets a full Manual J load calculation, Manual D duct design, and equipment selection based on calculated requirements, not guesswork.
Why Square-Footage Sizing Falls Short
The most common shortcut in residential HVAC is sizing equipment by square footage. A builder takes the floor area, divides by 500, and picks a unit. For a 2,000-square-foot home, that gives you 4 tons. It might be right. It also might be a full ton too large or half a ton too small, depending on variables that square footage alone doesn’t capture.
A home with tall ceilings, large west-facing windows, and minimal insulation has a dramatically higher cooling load than one with standard 9-foot ceilings, small windows, and spray foam insulation, even at the same square footage. In Louisiana, where cooling is the dominant load and humidity complicates everything, those differences translate directly into comfort and energy costs.
Manual J: The Engineering Approach
A Manual J load calculation accounts for every factor that affects heating and cooling demand:
- Wall and ceiling insulation R-values
- Window area, orientation, and glass type (Low-E, double-pane, etc.)
- Ceiling height and volume
- Roof material and color
- Number of occupants
- Kitchen appliance heat output
- Infiltration rate based on construction quality
The result is a precise cooling and heating capacity target in BTUs that determines what equipment to install. This number is specific to your house. Two homes on the same street in Sunset, with different orientations and window packages, will yield different load calculations and potentially require different equipment.
Ductwork That Performs from Day One
Equipment sizing only delivers results if the duct system can distribute the conditioned air properly. Manual D calculations determine the correct size for every trunk line, branch run, and return air path based on the volume of air each room needs.
Common Duct Design Mistakes
Single central return. Budget-driven builders sometimes install one large return grille near the air handler and call it done. When bedroom doors are closed, those rooms pressurize. Air can’t return to the system, so cooling delivery drops. Occupants feel warm even though the system is running. Each bedroom needs either a dedicated return duct or transfer grilles above the door to allow air back to the central return.
Excessive duct runs through the attic. In Sunset, attic temperatures climb past 140 degrees in summer. Long ductwork runs through that space lose significant cooling capacity before air reaches the register. Positioning the air handler centrally and keeping branch runs short makes a measurable difference in both comfort and efficiency.
Improper connections and sealing. Leaky duct joints dump conditioned air into the attic. In new construction, there’s no reason for duct leakage. Every connection should be mechanically fastened and sealed with mastic or approved tape.
Humidity: The Variable Most Builders Ignore
Louisiana’s building code sets minimum efficiency requirements for HVAC equipment, but it doesn’t require dedicated humidity management. In St. Landry Parish, that’s a gap.
A standard air conditioning system removes humidity as a byproduct of cooling. During the peak of summer, when the system runs for long periods, this works reasonably well. But during the shoulder seasons, when outdoor temperatures drop to the 70s while humidity stays in the 80s, your AC doesn’t have a reason to run. The humidity climbs indoors, and there’s nothing to bring it back down.
Two solutions work best when designed into new construction:
Variable-speed equipment runs at reduced capacity for extended periods, maintaining consistent dehumidification even when the cooling load is light. This addresses shoulder-season humidity without overcooling the house.
Whole-home dehumidifiers operate independently of the cooling system, removing moisture without affecting temperature. They tie directly into the duct system during construction, which is far simpler and less expensive than a retrofit installation.
Bringing It All Together
The advantage of new construction HVAC is total control. You’re not working around existing conditions or compromising with previous installations. Every element, from equipment placement to register location to thermostat wiring, gets designed for your specific home.
Building in Sunset or the surrounding area? Call F & R Air Conditioning at (337) 893-5646 before your plans are finalized. The earlier we’re involved, the better the system performs.