Is Manual J Required for an HVAC Permit?
By Danish Javaid, founder & editor · Published
Whether Manual J is required for an HVAC permit depends on the locally adopted code, amendments, and project scope. Many residential code pathways require documented loads and equipment selection, but there is no single nationwide submittal rule for every replacement. Ask the building department what your specific project must submit before ordering equipment.
Where the requirement comes from
There is no single national law that says “you must have a Manual J.” The requirement is inherited through model codes that states and local jurisdictions adopt. Model codes such as the IECC and the IRC include load-based equipment-sizing provisions, commonly referencing ACCA Manual J for the load and Manual S for equipment selection, or approved alternatives. A model-code edition does not become the governing rule everywhere at once. States and local jurisdictions adopt editions and amendments, and replacement, new-construction, and addition scopes can be treated differently. Enforcement also varies: some offices review a load report during plan review, others only check the permit application.
Confirm the rule for your address
- Describe the project precisely: like-for-like replacement, fuel conversion, added rooms, new system, or altered ducts.
- Ask which code edition and local amendments apply.
- Request the current mechanical-permit checklist and accepted calculation methods.
- Ask whether a block load, room-by-room report, Manual S selection, or Manual D duct design is required.
- Confirm who may prepare and sign the documents and whether a professional seal is required.
How project type can change the answer
| Project type | What to ask the permit office |
|---|---|
| New construction | Whether a load report is part of the energy-compliance or mechanical submittal, and what detail (block or room-by-room) is expected |
| Addition or newly conditioned space | Whether the new load must be documented and how the existing system is treated |
| Full system replacement with changed capacity | Whether a load calculation is required rather than a like-for-like swap |
| Like-for-like replacement | Whether the office waives, accepts a lighter submittal, or still wants documentation |
| Component repair | Usually whether a permit is needed at all; a repair that does not change capacity may be treated differently |
A load report and equipment selection are different
Manual J establishes heating and sensible/latent cooling loads. Manual S uses manufacturer performance to select the equipment. Manual D handles residential duct design. A tonnage printed on a quote does not demonstrate all three. If the jurisdiction requests an equipment schedule, include the exact indoor and outdoor models and design-condition capacity data. Commonly cited Manual S limits are about 95–115% of the total cooling load, with heat pumps up to about 125% in heating-dominated climates and furnace output about 100–140% of the heating load; check the applicable edition and local rules rather than relying on those figures alone.
What a reviewer may check
Plan reviewers generally confirm that a coherent report exists and that the proposed equipment matches it, rather than recalculating the load. Use this as a preparation checklist.
| Report detail | What to review |
|---|---|
| Project identity | Correct address, rooms served, preparer, report date |
| Design conditions | Accepted local weather and indoor setpoints |
| Building inputs | Dimensions, insulation, glazing/orientation, air leakage |
| Outdoor air and ducts | Documented ventilation and distribution assumptions |
| Loads | Heating plus separate sensible, latent, and total cooling |
| Equipment | Matched models and selection performance |
| Distribution | Room airflow and duct documentation when required |
Design temperatures should reflect the project’s actual location, not a default city elsewhere; see the guides on design temperatures and climate zones. For a line-by-line walkthrough of the figures on a report, see how to read a Manual J report.
Software branding is not a permit approval
Check ACCA’s current approved-software information if the submittal requires approved software. A vendor logo or phrase such as “Powered by Right-Suite” is not an ACCA certification stamp. Approval applies to the relevant software implementation, not to every input entered by a user. The authority reviewing the project decides whether the submitted package meets its requirements.
This site’s free Manual J calculator produces an estimate. It does not replace a full documented Manual J report, establish professional licensure, or guarantee acceptance. A printed calculator result should not be represented as a sealed engineering document.
How to obtain a report
If you are a contractor
Run the load in software that meets the jurisdiction’s requirements, using measured building data, and keep the report with the equipment selection and duct design. The same documentation supports the permit package and your own sizing decisions.
If you are a homeowner
You can ask the contractor for the report or commission one from an independent designer or a load calculation service, which can be useful when a contractor cannot provide one or you want an independent check. Before engaging anyone, gather clean room dimensions, window areas, and insulation details using the HVAC load calculation worksheet. Then run a quick estimate with the Manual J calculator to see whether a quoted size is in a plausible range; it is not a formal submittal.
Rebates have their own requirements
A utility or state program may require load documentation, approved contractors, specific equipment, or an inspection even when a permit office asks for different documents. Confirm those requirements separately. Federal §25C credits are not available for equipment placed in service in 2026; do not infer a current incentive from an old permit checklist or tax-credit article. Details of what changed are in the heat pump credit guide.
If the permit office requests corrections
Ask for written review comments, give them to the designer, and make revisions traceable to the project. If insulation, windows, or equipment change after approval, ask whether revised loads and selection must be submitted. Retain the final approved report, equipment schedule, permit, inspection record, and startup documentation with the house records.
Continue with: Load calculation services; Read the report; Manual J estimate.
References and verification
ACCA Manual J; ACCA Manual S; ACCA Manual D; IRS: home energy credit expirations; DOE Building Energy Codes Program.
Calculation guidance is reviewed against our published methodology. To report an error or request a correction, use the contact page.