Direct Answer
The Limitations section of a Miami-Dade County Notice of Acceptance (NOA) explains the conditions, restrictions, and installation requirements that must be followed for an approved roofing product or assembly to remain within the scope of its approval.
When reviewing a Miami-Dade NOA, contractors should look for restrictions on roof deck type, maximum design pressure, building height, permitted applications, installation methods, fire classification, and required quality-control procedures. These limitations determine whether the approved product or assembly is suitable for the specific project.
**The key rule is to match the limitations to the actual roof installation.** A product may have an active NOA but still be unsuitable for a particular building if the roof configuration, attachment method, substrate, or design pressure falls outside the approved conditions.
1. Start by Identifying the Exact Approved System
Before reading individual limitations, confirm that the NOA covers the product and assembly being proposed.
Check the following information:
- Manufacturer and product name: Confirm the exact product, model, and components.
- NOA number and expiration date: Verify the approval’s status and applicable code edition.
- Specific system description: Identify the approved roof assembly, including the deck, insulation, membrane or covering, and attachment method where applicable.
- System drawings: Review the details and fastening schedules that apply to the selected assembly.
Do not rely only on the NOA cover page. The detailed system pages and their limitations may contain restrictions that are not obvious from the summary.
2. Understand the Main Types of Limitations
Maximum Design Pressure
Maximum design pressure indicates the pressure limit associated with the approved roofing system. It is commonly expressed in pounds per square foot (psf).
Compare the applicable pressure rating for the selected system with the project’s required design pressures. Check the pressure rating on the actual system page rather than assuming that a maximum value printed elsewhere in the NOA applies to every assembly.
Also review any restrictions on pressure zones, enhanced fastening, and calculations. A system’s approval cannot automatically be extended beyond its listed rating through assumptions or unapproved changes.
Roof Deck and Substrate Restrictions
The NOA may approve an assembly only for specific substrates, such as a particular steel deck, concrete deck, or wood deck configuration.
If the building has a different deck type, thickness, profile, or substrate condition, do not assume the approval covers it. Confirm whether another approved system or an accepted alternative is needed.
Building Height and Exposure Restrictions
Some NOAs limit the height of the building or the conditions under which the product may be installed. Other restrictions may relate to the roof configuration or exposure.
Check these limitations against the actual building. A product approved for a lower roof should not automatically be specified for a taller structure without verifying the applicable approval conditions.
Installation and Attachment Requirements
Limitations may specify required fasteners, fastening spacing, adhesive application, flashing details, substrate preparation, or other installation conditions.
For example, a roof membrane approved for a particular fastening pattern cannot automatically be installed with fewer fasteners or a different attachment method. Substituting a similar-looking component does not establish that the resulting assembly remains approved.
Fire Classification
An NOA may explicitly state that fire classification is not included in the acceptance. If so, the NOA alone does not establish the roof’s fire rating.
Follow the document’s instructions for verifying the applicable fire classification and confirm that the complete proposed assembly satisfies the project’s requirements.
Product Use and Application Restrictions
Some limitations prohibit use over certain existing roof coverings, restrict exposure before installation of subsequent layers, or require particular weather conditions or approved applicators.
These restrictions can determine whether a product is suitable for a new roof, reroofing, recover, repair, or maintenance application. Verify that the intended use is expressly permitted.
3. How to Review a Limitation Step by Step
- Read the complete limitation. Do not interpret a sentence or numbered item without its conditions and exceptions.
- Identify the requirement. Determine whether it concerns pressure, substrate, installation, fire classification, labeling, or another restriction.
- Compare it with the project. Check the actual deck, building height, roof assembly, design pressures, and proposed installation method.
- Review the associated drawings. Confirm that the fastening schedule, attachment details, and component combinations match the selected system.
- Resolve any mismatch before installation. Consult the manufacturer, design professional, or building official about an appropriate approved alternative.
- Include the applicable documents in the permit package. Follow the local building department’s submission requirements.
4. Example: Why a Limitation Can Change a Roofing Decision
Suppose an NOA covers a membrane roofing system over a specified steel deck and lists a maximum design pressure for that particular assembly. The proposed building has a different deck configuration, or the required design pressure exceeds the system’s rating.
Even if the product name matches the NOA, that does not establish that the proposed installation is covered. The contractor must identify an assembly approved for the actual conditions or obtain an appropriate determination from the authority having jurisdiction.
Similarly, if a limitation excludes a particular recover application, the contractor should not assume that the product can be installed over an existing membrane simply because the product itself is approved.
5. What If a Limitation Is Unclear?
Do not guess or disregard the restriction. Ask the manufacturer or approval holder for clarification, consult the project’s design professional, and confirm the proposed approach with the local building official when necessary.
Any alternative assembly, substitution, or installation detail must be supported by the applicable code and approval process. Written clarification is especially useful when the interpretation affects design pressures, fastening, substrate compatibility, or permit acceptance.
Bottom Line
The Limitations section is the rulebook for how a Miami-Dade NOA may be used. Review it alongside the specific system description, design-pressure information, installation drawings, approval status, and applicable fire classification documentation.
A valid NOA is not blanket permission to install a product in any configuration. The proposed roof must match the approved assembly and satisfy the restrictions and code requirements that apply to the project.
