Serving Ventura and LA County
Years of Experience
An HVAC load calculation measures how much heating and cooling your specific home actually needs, room by room. HVAC Inspections Los Angeles performs on-site Manual J load calculations across Los Angeles and Ventura Counties — a NATE-certified inspector scans and measures your home in person and delivers a written, room-by-room sizing report you can use for a replacement decision, a permit file, a heat pump conversion, or a second opinion on a contractor’s bid. Pricing is flat: $795 for homes up to 2,500 sq ft and $995 for 2,500–4,000 sq ft. Quotes for larger homes are free.
Key takeaways
- Manual J, published by the Air Conditioning Contractors of America (ACCA), is the ANSI-recognized standard for residential load calculation — it sizes equipment from the building itself, not from square-footage rules of thumb.
- Our fee is flat: $795 for homes up to 2,500 sq ft and $995 for 2,500–4,000 sq ft, including the on-site scan and the written room-by-room report.
- California’s Title 24 energy code makes documented load calculations part of the compliance paperwork for many HVAC change-outs and new installations in Los Angeles.
- Right-sizing matters most on heat pumps: an oversized or undersized heat pump loses the comfort and efficiency the conversion was supposed to deliver.
- We measure the home in person with a LiDAR scan, using Conduit Tech — software that ACCA lists as approved for full Manual J residential load calculations. Every room, window and ceiling height is captured from the scan rather than estimated from plans or photos. Virtual assessments are available when an on-site visit isn’t practical.
Why load calculations matter in Los Angeles
Los Angeles homes are unusually hard to size by shortcut. A 1950s beach-city home under the marine layer, a 1970s San Fernando Valley ranch that bakes at 100°F+ in summer, and a remodeled Spanish bungalow with three generations of additions all carry completely different heating and cooling loads — even at identical square footage. Contractors who size a new system by matching the old equipment inherit whatever mistake was made decades ago.
The stakes have risen with California’s electrification push. Heat pump incentives through programs like TECH Clean California have made conversions common across LA, and a heat pump only delivers its promised comfort and efficiency when it’s sized to the actual load. Meanwhile, Title 24 compliance paperwork for HVAC change-outs commonly requires documented load calculations — inspectors and permit offices increasingly ask for the numbers, not a guess.
What our load calculation includes
| Step | What we do | What you receive |
|---|---|---|
| On-site LiDAR scan | Scan each room to capture conditioned area, ceiling heights, window and door areas, orientation, and shading | A load model built from your home, not assumptions |
| Envelope assessment | Document insulation levels, construction type, and air-leakage factors | Accurate inputs for the heating and cooling load |
| Duct and distribution review | Evaluate duct location, condition, and layout feeding each room | Sizing that accounts for real delivery losses |
| Manual J calculation | Run the ACCA Manual J methodology in Conduit Tech, ACCA-approved software, with Los Angeles design conditions | Room-by-room heating and cooling loads in BTU/h |
| Written sizing report | Summarize total and per-room loads with equipment sizing guidance | A document you can hand to a contractor, permit office, or lender |
The report is flat-fee and findings-based. We do perform HVAC work, but you are never obligated to use us for anything the report supports — most clients use it to check a contractor’s proposal, right-size a replacement, or complete a permit file. If your project is part of a purchase, the calculation pairs naturally with an HVAC escrow inspection; if you’re weighing a conversion, see our home electrification services.
What a Manual J load calculation costs in Los Angeles
A Manual J load calculation from HVAC Inspections Los Angeles costs $795 for homes up to 2,500 square feet and $995 for homes between 2,500 and 4,000 square feet. The fee is flat and covers the on-site LiDAR scan, the Manual J calculation, and the written room-by-room report.
| Home size (conditioned area) | Flat fee | What is included |
|---|---|---|
| Up to 2,500 sq ft | $795 | On-site LiDAR scan, Manual J calculation, written room-by-room report |
| 2,500–4,000 sq ft | $995 | On-site LiDAR scan, Manual J calculation, written room-by-room report |
| Larger homes | Call for a quote | Scoped to the home. Quotes are always free: (310) 465-3822 |
The calculation is run in Conduit Tech, which appears on ACCA’s list of approved Manual J software. ACCA states that only approved software produces results that comply with its design standard, which is what a Los Angeles permit office or rebate program is checking for.
Why an In-Person Calculation Beats a Remote One
Most load calculation services online never see your home — they build the model from floor plans, photos, and your own answers about insulation and windows. Those inputs are exactly where older Los Angeles homes hide their surprises: undocumented additions, missing insulation, replaced windows, and ductwork that was rerouted three owners ago. A NATE-certified inspector scanning and measuring the property in person catches what a questionnaire can’t, and the report holds up when a contractor or permit office questions it.
When an on-site visit isn’t practical, we also offer virtual assessments — guided remotely, documented in writing, performed under CA Contractors License #1075723.
When you need a load calculation
- Replacing a system — the single biggest sizing mistake is copying the old unit’s size. If it was wrong then, it stays wrong.
- Converting to a heat pump — right-sizing determines whether the conversion delivers on comfort, efficiency, and incentive requirements.
- Pulling a permit — when the compliance paperwork asks for documented loads, this report answers it.
- Comparing contractor bids — when one bid says 3 tons and another says 5, a measured calculation settles it before you spend.
- Chasing comfort problems — rooms that never cool, systems that short-cycle, or humidity issues often trace back to a sizing mismatch.
Frequently asked questions
How much does a Manual J load calculation cost?
Our Manual J load calculation is a flat $795 for homes up to 2,500 square feet and $995 for homes between 2,500 and 4,000 square feet, including the on-site LiDAR scan and the written room-by-room report. Larger homes are quoted individually, and quotes are always free. Remote, plan-based services cost less because nobody measures the property — an on-site, measured calculation is what makes the numbers defensible. Call (310) 465-3822 to schedule.
Can I do my own Manual J calculation with a free calculator?
Free online calculators can give a rough range, but they rely on default assumptions about insulation, infiltration, and windows. Permit offices, lenders, and incentive programs generally want documentation produced by a qualified professional, and contractors rarely warranty sizing based on a homeowner’s own estimate.
What is the $5,000 rule in HVAC?
It’s a common repair-or-replace heuristic: multiply the system’s age by the repair cost, and if the result exceeds $5,000, replacement usually makes more financial sense than the repair. If you land on the replace side, a load calculation is the first step to buying the right-sized system instead of repeating the old one.
How long does a load calculation take?
The on-site scan and measurement typically take one visit, and the written room-by-room report follows once the calculation is complete. Timing depends on the size and complexity of the home — we’ll give you a specific turnaround when you book.
Is a load calculation the same as an HVAC inspection?
No — an inspection evaluates the condition and operation of the equipment you have; a load calculation determines the capacity your home needs. They’re complementary: during a purchase or replacement, the inspection tells you what’s there and the calculation tells you what should be. Our inspection checklist shows exactly what the condition side covers.
Get the Right Size, In Writing
On-site Manual J load calculations · $795 up to 2,500 sq ft · $995 for 2,500–4,000 sq ft · Los Angeles & Ventura Counties
HVAC Inspections Los Angeles · 1105 6th St, Hermosa Beach, CA 90254 · Mon–Fri 8am–6pm, Sat 9am–12pm · CA License #1075723
