A structural letter of compliance is a written certification from a licensed professional engineer stating that a specific element, condition, or installation meets the applicable structural requirements of the building code. Building departments request these letters when they need professional confirmation that structural work is code-compliant, but a full set of stamped drawings is not required or appropriate. Our structural engineering services include compliance letters for projects in all 50 states.
How a Compliance Letter Differs From Stamped Drawings
Stamped drawings are graphic documents that show what is to be built or what exists. A compliance letter is a written statement from a PE that certifies a specific condition or scope of work meets code. They serve different purposes and are not interchangeable, but building departments sometimes accept a letter in place of full drawings when the scope is limited or the work is already complete.
A compliance letter is not a substitute for engineering design on complex projects. When a building requires a new structural system, additions, or significant modifications, stamped drawings with full engineering calculations are the appropriate deliverable. A compliance letter is appropriate for relatively simple conditions where the PE can observe or analyze the situation and certify it against a specific code provision.
The difference matters because it affects what the PE must do to prepare each document. For stamped drawings, the engineer performs full design calculations and produces detailed graphic documents. For a compliance letter, the engineer evaluates the existing condition or installation and makes a professional judgment about code compliance. Both require a PE license in the applicable state and a clear understanding of the relevant engineering standards.
When Building Departments Request Compliance Letters
Existing Condition Certification
When a building changes ownership, undergoes a change of use, or receives a complaint, the building department may require certification that the existing structure meets current code requirements. This is common in older buildings where the original permit documentation is incomplete or unavailable. The PE inspects the visible structural elements, documents member sizes and conditions, and certifies that the existing structure meets the applicable code provisions for the proposed use.
Minor Work Without Full Drawing Sets
Some jurisdictions accept a compliance letter in lieu of full stamped drawings for small scope items: a single beam modification, a minor opening in a non-load-bearing wall confirmed to be non-structural, or the installation of lightweight equipment on a roof structure that clearly has adequate capacity. This is most common in jurisdictions with flexible plan check processes for low-risk work. Our team understands when a letter is appropriate versus when specialty structure drawings are required.
Post-Inspection Clarification
An inspector who encounters field work that differs from approved drawings may request a compliance letter from the engineer of record confirming that the as-built condition meets structural requirements. This is common when field conditions required minor deviations from the approved documents and the deviation was structurally acceptable even if it was not shown on the original drawings.
What the Letter Must Contain
A proper structural compliance letter includes the project address and description, a clear statement of what was evaluated, the code provision or standard the evaluation was based on, a description of the methodology used (field observation, calculation review, reference to design documents), the PE’s professional judgment that the condition meets or does not meet the stated requirement, and the PE’s signature, license number, and stamp.
The letter should be specific about what is being certified and what is not. A letter certifying that a specific beam was observed to be adequately sized for the loads it carries does not certify the entire building structure. This precision protects the building owner, the PE, and the jurisdiction. Our engineering team writes compliance letters that are precise, well-documented, and acceptable to the jurisdictions we work in.
What the Letter Cannot Do
A compliance letter cannot certify conditions the PE cannot observe or analyze. Hidden structural elements, conditions behind finishes, or underground work require investigation before a PE can certify them. If a compliance letter is requested for conditions that cannot be verified without destructive investigation, the PE should say so clearly rather than certify conditions they cannot confirm.
A letter also cannot certify that work done by others meets code if the PE has no basis for that judgment. The PE must have direct knowledge of the work either through design, observation, or review of complete and reliable as-built documentation.
Typical Turnaround and Process
For straightforward compliance letter requests where the information is available and the condition can be evaluated without a site visit, we typically deliver letters within one to three business days. Cases requiring field verification take longer depending on site access coordination. Submit your request through rightangleeng.com/get-started with the project address, a description of what needs to be certified, and any relevant photos or drawings.
Frequently Asked Questions
Is a compliance letter the same as a permit?
No. A compliance letter is a professional certification document. A permit is issued by the building department and authorizes specific construction work. In some cases, a compliance letter is required before a permit can be issued or finaled. In other cases, a permit was obtained for prior work and a compliance letter is now needed to certify that the work was completed in accordance with code.
Who can write a structural compliance letter?
Only a licensed professional structural engineer or civil engineer with structural experience in the applicable state can sign and stamp a structural compliance letter. The PE must be licensed in the state where the project is located. We hold PE licenses in all 50 states.
How long does it take to get a compliance letter?
Most straightforward compliance letters are delivered within one to three business days once we have all necessary project information. Letters requiring site investigation take longer depending on site access. Rush turnaround is available for time-sensitive permit situations.
Need a Structural Compliance Letter?
We provide PE-stamped structural compliance letters for projects across all 50 states. Submit your request at rightangleeng.com/get-started with your project details to get started.
References
International Building Code. (2021). International Code Council. Country Club Hills, IL.
National Society of Professional Engineers. (2019). NSPE Code of Ethics for Engineers.
American Society of Civil Engineers. (2017). ASCE Policy Statement 418: The Role of the Engineer of Record.