DUCTWORK & SMART ZONING IN LEHI

Lehi homes are bigger than the typical Wasatch Front home — 2,800 to 4,500 sqft is normal in Traverse Mountain, Holbrook Farms, and Skye Estates, with 5,000+ sqft custom builds in Cold Springs Ranch and the upper Traverse Mountain loop. Bigger square footage means longer trunk runs, more branch chases, and more flex duct routed through unconditioned attic space. Builder-grade flex duct installs in 2014-2018 cohort Lehi homes were rushed — joints taped instead of mastic-sealed, strap-and-screw transitions skipped, insulation sloppy. Eight to ten years in, those joints are starting to leak material amounts of conditioned air into the attic.

The other Lehi-specific issue: smart-zoning damper systems. Most dual-zone Lehi builds have a single furnace and AC feeding two zones (main floor + upper floor, typically) through a damper assembly in the trunk. Builder zoning panels were Honeywell TrueZone or EWC Ultra-Zone with basic 7-day thermostats. The dampers themselves are mechanical — actuators that open and close — and they wear. Eight years in, we're seeing the first cohort of damper actuator failures, plus thermostats that homeowners want to upgrade to smart-home-integrated controls.

What duct problems cost in real dollars

A typical 3,200 sqft Lehi home with moderately leaky ductwork (15-25% loss) is paying an extra $400 to $800 per year on heating and cooling. Over a decade, that's $4,000 to $8,000 in wasted gas and electric. A proper seal-and-repair plus damper recalibration job — usually $2,200 to $5,500 depending on access and scope — pays back in 4 to 8 years on utility savings alone. Comfort improvement is immediate, especially on the upper-floor zone of a dual-zone system.

Common Lehi ductwork problems

• Disconnected flex duct at plenum — most common single issue, tape-and-strap failure on 2014-2018 builds
• Damper actuator failures — 8-12 year wear item on mechanical dampers in builder-grade zoning systems
• Crushed or kinked flex duct — tight turns in attic chases, things dropped during home inspections
• Undersized return for upper floor — common builder corner-cut on dual-zone homes, upper zone chokes on airflow
• Leaky sheet metal joints at the trunk — older mastic dries and cracks, trunk-to-plenum splits
• Missing R-8 insulation in attic — code requires R-8 on attic ducts, builder grade often runs R-4 or less
• Unbalanced airflow between rooms — common after furniture rearranges or finished-basement additions

How we diagnose ductwork issues in Lehi

Two tools do most of the work. A pressure-based blower door and duct blaster test measures total leakage in cubic feet per minute at 25 pascals — energy-code metric that quantifies leakage objectively. Then visual inspection with lighted probe and camera, pulling insulation to look at joints, checking flex runs, measuring trunk sizes against load calculations. On dual-zone systems, we also pull every damper to verify actuator operation and bypass settings.

Sealing options

Manual sealing with mastic and foil tape — works where we can access the joints. Mastic brushed onto every seam, foil-backed butyl tape on major connections, strap-and-screw on flex-to-rigid transitions. $1,800 to $3,800 for a typical Lehi home depending on accessibility.

Aeroseal interior sealing — polymer aerosol pushed through the duct system under pressure. Seals from inside without needing exterior access. Works on attic flex, inside wall chases, anywhere traditional sealing can't reach. $2,800 to $4,800 for most Lehi homes. Best single-biggest-impact intervention.

Replacement of bad sections — collapsed or aged flex replaced with new insulated flex or rigid sheet metal. $15 to $35 per linear foot of replacement flex installed.

Smart-zoning damper systems

We install and retrofit zoning systems on existing single-zone homes (rare in Lehi but it happens), and we replace failed builder-grade zoning panels with newer smart-home-integrated systems. Honeywell TrueZone HZ432, EWC Ultra-Zone, and the Trane / Carrier OEM zoning panels for communicating systems. Thermostat side integrates with Home Assistant, Hubitat, SmartThings, Google Home, or Apple Home — your choice. We can ship a Home Assistant config back to you if you're running your own automation.

New construction and full duct design

For major remodels, additions, or complete duct replacement, we do Manual D duct design alongside Manual J load calc. The whole system gets sized correctly: trunk sizes, branch runs, balanced register sizing per room, enough return capacity for actual equipment. Most existing Lehi residential ductwork was rules-of-thumb and builder convenience. Doing it right on a remodel pays back in every category.

Registers, grilles, and balancing

Final step on most Lehi ductwork projects is room-by-room airflow balancing. Registers have dampers; we adjust them to deliver right volume per room based on heat load. Bigger south-facing rooms get more air in summer; colder north-facing rooms more in winter. On systems with zone dampers, we calibrate damper positions and verify bypass operation. Well-balanced system feels even across the house and equipment cycles appropriately.