Why a Los Feliz duct redesign and air balancing starts at the air path, not the brand
Los Feliz brings a specific comfort puzzle: historic homes, hillside rooms, apartments, and large-window remodels. The health and comfort pressure is hillside heat, older ducts, pet dander, smoke days, and quiet bedroom expectations. The install pressure is preservation-sensitive routing, ductless placement, filter access, and system labeling. That combination is why Breathe LA 365 starts with room mapping instead of a generic equipment pitch. Equipment selection in Los Feliz only matters once the room outcome is named: a primary bedroom that holds 70°F at 11 p.m., a nursery without direct supply draft on the crib, a clean room ready for the next AirNow PM2.5 spike, or a home office that holds ±1°F across a workday.
The technical anchor for duct redesign and air balancing: Manual D total external static budget allocates 0.50 in. w.c. for PSC blowers, 0.80 for ECM. Friction rate FR = (TESP × 100) / Total Effective Length runs typically 0.06–0.10 in. w.c. per 100 ft. Return-air free-area rule is 144 sq in (1 sq ft) net per ton. Insulation requirement Title 24 §150.0(m)1: R-8 minimum on supply and return in unconditioned spaces (CZ 1–16, CZ 6 may use R-6).
Marcus runs the static-pressure, supply-CFM, and return-free-area triangle before any quote leaves the office. Audit takes 60–90 minutes onsite; written engineering report follows within 48 hours.