Key takeaways
- The five solar permit documents word the sign-off differently: 3 say "stamp", 4 say "signed" and 2 mention a letter.
- Only two of the five name a discipline such as civil or structural, and three name the state of licence.
- In the state rules we read, the state sets what a seal must show. Texas asks for seal, signature and date. California sets a seal at least 1.5 inches across.
- Versions matter: Larimer’s November 2023 guidelines ask for a PE letter, but its January 2026 checklist does not mention one.
- Our invented budget has 40 jobs a month, 25% stamped at 200 USD per stamp and 10% of stamped jobs re-stamped. That gives 11 stamps and 2,200 USD a month (placeholders, not prices).
To get an engineer-stamped plan set, see the best solar plan set services.
PE stamp at a glance
A PE stamp is an engineer’s sign-off. It is not a document. The state licensing board sets what it must show. The AHJ picks which sheets need it.
| Item | Detail |
|---|---|
| What it is | A seal, signature and date from an engineer, usually one licensed in the state of the job. |
| What the seal must show | Set by each state. Texas (22 TAC 137.33): seal, signature and date. California (16 CCR 411): name, certificate number and branch, in a seal at least 1.5 inches across. |
| Where it matters | In the documents we read: structural sheets and calculations, and engineer letters for roofs. LA County asks for the preparer’s signature and licence on electrical drawings. |
| Standard or rule | No national solar rule. State engineering law plus each AHJ’s checklist. |
| In software | Plan-set services route drawings to an engineer. Design tools mostly do not stamp. |
Why does a PE stamp matter for installers?
A missing or wrong stamp sends the plan set back. That delays the permit. A stamp also costs engineer time on every job that needs one.
The rule often hides in the detail. Portland asks for an engineer "registered in Oregon". Santa Clara asks for a "California-licensed" civil or structural engineer. An engineer from another state, or in the wrong discipline, can fail a check. The drawings can still be right.
Oregon law ties the seal to responsibility. ORS 672.020(2) says a registrant’s signature and stamp "constitute a certification that the document was prepared by the registrant". See the permit plan set page for the sheets a stamp covers.
How do engineers get licensed?
Each state licenses its own engineers. NSPE lists a degree, the FE exam, generally four more years of experience, then the PE exam. It says state laws "vary from state to state".
Figure 1. The five documents differ in how they word the sign-off.
What do states and AHJs say about PE stamps?
Each source below says something different. None is a national rule. The first three rows are state engineering rules about seals. The rest are AHJ papers about solar. Quotes are as read in October 2026.
State rules about seals.
| Place and source (date as printed) | What it says |
|---|---|
| California, board rule 16 CCR 411 (latest amendment we found: operative 1-1-2014) | Seal at least 1 1/2 inches across, with name, certificate number and branch. "The signature may be applied to the documents electronically." |
| Texas, 22 TAC 137.33 (amended, effective 7/3/2022) | "License holders shall only seal work done by them" or under direct supervision. Final work carries seal, signature and date. Electronic seals need security steps. |
| Oregon, ORS 672.020 (current through early 2026) | No person may practise or offer to practise engineering in the state "unless the person is registered". |
AHJ papers about solar.
| Place and source (date as printed) | What it says |
|---|---|
| Santa Clara, CA, expedited PV guide (revision 07-2023) | "For non-qualifying systems, provide structural drawings and calculations stamped and signed by a" California-licensed civil or structural engineer. |
| Los Angeles County, CA, plan review list (30 March 2023) | Structural plans and calculations "signed by a licensed architect or civil engineer", unless the listed conditions are met. |
| Portland, OR, engineered systems (undated, copyright 2018-2026) | "Drawings that depict structural information shall be stamped/signed by an engineer registered in Oregon." |
| Larimer County, CO, submittal guidelines (November 2023) | "State of Colorado licensed Professional Engineer’s letter addressing the roof or wall", with snow and wind loads and anchoring outlined. |
| Reno, NV, solar guidelines (updated 07/01/2025) | "Structural plans and details shall be stamped by the engineer." Calculations stamped, signed and dated by the engineer of record. |
| New York City, DOB solar FAQ (copyright 2025) | "Owners must hire a Registered Design Professional who is registered with the Department to submit plans." |
What the sources leave out.
- California: nothing about solar or when a seal is needed. Rubber stamps of the signature are barred (411(f)).
- Texas: nothing about solar. The rule exempts some holders under the Occupations Code. The exemptions are not listed in the text read.
- Oregon: exemptions are in another section, which was not opened.
- Santa Clara: the qualifying checklist itself is not repeated here.
- Los Angeles County: no wet stamp, engineer stamp or state named. Electrical drawings need the preparer’s signature and licence information. Conditions are on the structural loads page.
- Portland: no electrical stamp and no non-engineered route described.
- Larimer County: the January 2026 checklist does not mention the letter or a stamp.
- Reno: no PE or Nevada licence named. The cover page is "stamped by the contractor".
- New York City: no seal or stamp rule. Tax abatement needs certification by an architect or engineer.
This page gives no kW thresholds. Company blogs list them by state, but did not tie them to a state or AHJ page that could be opened. Confirm limits with your AHJ.
What is the difference between a stamp, a seal, a signature and a letter?
A stamp or seal is the engineer’s mark. The signature and date go with it. A letter is a short, separate document, often for a roof or racking. It carries the same mark.
Wording differs by AHJ. Santa Clara says "stamped and signed". LA County says "signed". Larimer’s guidelines say "letter". Reno also asks for a "stamped verification letter" on an existing roof. Read the exact words. Then ask the AHJ what it accepts.
Not all AHJs accept digital seals. GreenLancer (28 September 2026) calls one an electronically signed and sealed PDF. It says a scanned seal image pasted on a PDF is not a true digital signature. AHJs may accept either form. California’s rule allows an electronic signature. It bars rubber stamps of the signature. Texas allows electronic seals with security steps.
Structural and electrical stamps are separate asks. Portland’s page covers structural information only. The Santa Clara line we quote covers structural drawings. On electrical drawings, LA County asks only for the preparer’s signature and licence. See single line diagram and AHJ.
Stamp budget calculator
Enter your own jobs, share needing a stamp, fee and turnaround. Every starting value is a made-up placeholder. It is not a price or a rule. The table shows three cases from the same placeholders.
| Case (all placeholders) | Stamped jobs a month | All stamps a month | Spend a month (USD) | Spend per job, all jobs (USD) |
|---|---|---|---|---|
| Base: 40 jobs, 25% stamped, 200 USD fee, 10% of stamped jobs re-stamped | 10.0 | 11.0 | 2,200 | 55.00 |
| Half of jobs need a stamp (50%) | 20.0 | 22.0 | 4,400 | 110.00 |
| No re-stamps (0% of stamped jobs) | 10.0 | 10.0 | 2,000 | 50.00 |
Moving the stamped share from 25% to 50% doubles spend, from 2,200 to 4,400 USD. Re-stamping 10% of stamped jobs adds 1 extra stamp and 200 USD a month. It also raises the expected wait from 2.0 to 2.2 business days (turnaround placeholder: 2 days).
How solar software handles PE stamps
Of the four tools and services we checked, Aurora Plan Sets Service and GreenLancer supply a PE stamp. Unirac does so in part and Solargraf does not say. Aurora’s list of places it does not cover comes from a 2023 FAQ, so confirm your state.
| Software or service | Supplies a PE stamp? | Source and date read |
|---|---|---|
| Aurora Plan Sets Service | Yes | Aurora FAQ, posted 23 August 2023, modified 4 April 2024. May be out of date |
| GreenLancer | Yes | GreenLancer permit design page, undated, copyright 2026 |
| Unirac U-Builder | Partly | Unirac U-Builder page, copyright 2026, no update date |
| Solargraf | Not stated | Solargraf help article, 18 September 2024 |
Not stated: the page we read does not mention it. Partly: the stamp is listed only as a separate paid service. Here is what each company page says.
- Aurora Plan Sets Service: "Aurora integrates structural and electrical engineering stamps into the Plan Sets Service."
- Aurora exclusions: not offered in "New York City, Portland, OR, and Illinois" (stamps section of the 2023 FAQ, may be out of date). The same FAQ’s availability answer names only New York City. Priced by volume.
- GreenLancer: "Every project can include a PE stamp when the jurisdiction requires one."
- GreenLancer, engineer: the engineer "must be appropriately licensed in the state where the solar installation is located".
- Unirac U-Builder: the tool exports "State Certification letters". The page lists "PE stamps in all 50 states" under paid plan set services, not under the tool.
- Solargraf: the self-service plan set article does not mention a PE stamp, an engineer or a seal.
For services that route drawings to an engineer, see the best solar plan set services. For racking calculations that come with engineer letters, see the best solar mounting structure design software.
Common mistakes with PE stamps
FAQs
Does a solar installation need a PE stamp?
Only where the state or AHJ asks for one, and for structural sheets that is common. No national rule applies. All five documents we read mention a stamp, signature or letter on structural work for some systems. On non-qualifying systems, Santa Clara asks for a stamp from a California-licensed civil or structural engineer. LA County lets qualifying roofs skip structural calculations. Ask your AHJ which sheets it wants stamped.
Who can stamp solar plans?
An engineer licensed in the state where the building stands. Oregon law says no one may practise engineering in the state without registering. Portland names "an engineer registered in Oregon". Some AHJs also accept an architect. LA County does so for structural plans.
What is the difference between a structural and an electrical stamp?
The documents we read tie stamps to structural drawings, calculations and roof letters. None defines what an electrical stamp covers. On electrical drawings, LA County asks only for the preparer’s signature and licence information.
Is a digital PE stamp accepted?
Often, but check. California’s rule says a signature may be applied electronically. Texas allows electronic seals with security steps. GreenLancer says AHJs may accept either wet or digital. A pasted image of a seal is not a true digital signature.
How much does a PE stamp cost?
No fee is stated on this page, because we read no dated fee page. The 200 USD in the calculator is a placeholder. Aurora’s FAQ says only that plan sets are priced by volume. To compare written quotes, see the best solar plan set services. Then test a quote in the calculator above.
Related terms
- AHJ: the authority that adopts the code and decides what must be stamped.
- Permit plan set: the drawings and calculations a stamp covers.
- Structural loads: the roof loads an engineer checks.
- Single line diagram: the electrical sheet some AHJs want signed.
- SolarAPP+: an online platform that automates permit review.
Next step: to order an engineer-stamped plan set, compare the best solar plan set services. For racking calculations, see the best solar mounting structure design software.
Sources
All opened October 2026. Dates are as each page prints them.
- California rule 16 CCR 411, on Cornell LII (latest amendment we found: operative 1-1-2014).
- Texas rule 22 TAC 137.33, on Cornell LII (effective 7/3/2022).
- ORS 672.020, on oregon.public.law (current through early 2026).
- Santa Clara, expedited PV guide (revision 07-2023).
- Los Angeles County, solar plan review list (30 March 2023).
- Portland, engineered systems guidelines (undated).
- Larimer County, solar guidelines (November 2023, checklist January 2026).
- Reno, solar permit guidelines (updated 07/01/2025).
- NYC Buildings, solar FAQ (copyright 2025).
- NSPE, path to licensure (undated).
- GreenLancer, wet stamps (28 September 2026) and permit design page (undated).
- Aurora, Plan Sets FAQ (posted 23 August 2023, modified 4 April 2024, re-read 30 October 2026).
- Unirac U-Builder (copyright 2026) and Solargraf help (18 September 2024).
Last updated 30 October 2026. Next scheduled review: 30 January 2027.