Impact-Rated Windows and Doors in South Carolina: Code Requirements and Documentation
Updated: 3 days ago
Homes along the South Carolina coast face a significant risk from high winds and wind born debris during hurricanes and severe storms. In designated windborne-debris regions, exterior windows, glass doors and other glazed openings must be properly protected.
For homeowners, builders and contractors, choosing a product advertised as “impact rated” is only part of the process. The product must meet the standards applicable to the specific project, and the proper documentation must be available for review by the building official.
When Is Impact Protection Required?
Section R301.2.1.2 of the 2021 South Carolina Residential Code requires exterior glazing in buildings located within windborne-debris regions to be protected from windborne debris.
This protection can generally be provided through:
Impact-resistant windows and doors
Permanently installed impact-protection systems
Approved hurricane shutters or removable protective panels
Whether a particular property falls within a windborne-debris region depends on its location, applicable wind-speed criteria and exposure to the coastline. Not every home in coastal South Carolina is automatically subject to identical requirements, so the project’s design criteria and local jurisdiction should always be confirmed before products are ordered.
Which Standards Apply?
Under the current South Carolina Residential Code, glazed-opening protection must satisfy the Large Missile Test requirements of both:
ASTM E1886, which establishes the test procedure for exterior windows, doors and protective systems exposed to missile impacts and cyclic pressure
ASTM E1996, which establishes the performance criteria and missile classifications used during that testing
These standards work together. Documentation referencing only one of them may not provide enough information for approval. The project must also be designed using the applicable edition of ASCE 7, which establishes wind loads, wind speeds, exposure categories and other structural design criteria. Under South Carolina’s current 2021 code cycle, the referenced edition is ASCE 7-16. It is more precise to say that the building is designed according to ASCE 7-16 and that the window or door assembly is tested according to ASTM E1886 and ASTM E1996.
Choosing the Right Window or Door Manufacturer
The manufacturer matters, but so does the exact product line, glass package, size and installation method being used. Transform Charleston works with established window and door manufacturers including Marvin, Andersen and Simonton, giving homeowners options across different architectural styles, performance levels and budgets.
For example, Marvin and Andersen offer a broad range of premium window and door configurations that can work well for custom homes, historic-inspired renovations and larger architectural openings. Simonton is another strong option for replacement-window projects, with product lines designed to balance performance, efficiency and value.
However, choosing a reputable brand alone does not guarantee that every unit within that brand is approved for a particular coastal application. A Marvin, Andersen or Simonton window may be available in multiple glass packages, sizes and performance configurations, and only certain assemblies may meet the impact and design-pressure requirements for a specific project.
That is why product selection should be based on the exact requirements of the home rather than simply choosing a manufacturer and assuming every product in the line carries the same approval.
What Documentation Should Be Provided?
Manufacturers should supply documentation identifying the exact window or door assembly and demonstrating that it satisfies the required standards.
Acceptable supporting information may include:
Manufacturer product-approval documents
Test reports or evaluation reports
Installation instructions
Design-pressure ratings
ASTM E1886 and ASTM E1996 compliance information
Product labels, glazing etchings or certification markings
Documentation matching the product’s model, size, glass configuration and installation method
Major manufacturers such as Marvin, Andersen and Simonton typically provide technical documentation for their individual product series and configurations. Contractors should obtain the documentation associated with the exact units being ordered and keep it available throughout permitting and inspection.
For example, documentation for one Andersen window series should not automatically be assumed to apply to another Andersen series. The same applies to different Marvin or Simonton products, glass packages and installation configurations.
The product shown in the documentation must correspond with the unit installed on the home. A report for a similar product, different glass package or different installation configuration may not be sufficient.
Design Pressure Matters Too
Impact resistance and design pressure are related but separate considerations.
A window may have impact-resistant glazing while still needing to meet the positive and negative design-pressure requirements calculated for the home. Larger openings, different building heights and varying exposure conditions can all affect the required pressure rating.
This is another reason homeowners should avoid selecting windows based only on a general “hurricane” or “impact-rated” description.
Manufacturers such as Marvin, Andersen and Simonton offer many different configurations, and their allowable design pressures can vary by product series, size, glass type and installation method. The selected unit should therefore be reviewed against the project-specific requirements before it is ordered.
Leave the Product Labels in Place
Many manufacturers place important approval information on temporary window and door labels. Additional information may also be permanently etched into the glass, although the etching often uses proprietary names or codes that are difficult to interpret without the manufacturer’s supporting documents.
Installers should leave the informational labels attached to several representative units until the final building inspection has been completed. Removing every label too early can make it more difficult for the inspector to verify the installed products. For the smoothest approval process, the manufacturer, product series, applicable ratings and approval documents should also be identified in the permit package or approved plans. This becomes especially important when a project includes several different window or door types. A home may include a combination of fixed windows, operable windows, patio doors and larger architectural units, each with its own model information and performance ratings.
Preparing for the Next Code Cycle
South Carolina currently enforces the 2021 South Carolina Building Codes, which took effect January 1, 2023. These codes reference ASCE 7-16. The state is moving through the adoption process for the 2024 code cycle. Once the new codes become effective, applicable projects are expected to transition to ASCE 7-22. Contractors and homeowners should confirm the effective code edition with the permitting jurisdiction before ordering products, particularly for projects permitted near a code-cycle transition.
Product approvals and technical information from manufacturers may also be updated as standards and code requirements evolve. When considering products from Marvin, Andersen, Simonton or another manufacturer, contractors should make sure they are reviewing the documentation applicable to the current product and current code cycle rather than relying on an older report from a previous installation.
Avoiding Delays at Final Inspection
Most impact-protection approval problems are documentation problems - not necessarily product problems. Before installation begins, contractors should confirm that the selected windows and doors satisfy the project’s required impact rating, design pressures and installation conditions.
A strong compliance package should include:
The exact manufacturer and product series
Evidence of ASTM E1886 and ASTM E1996 compliance
Required positive and negative design-pressure ratings
Manufacturer-approved installation instructions
Documentation matching the installed size and configuration
Visible labels or glazing markings for field verification
Choosing established manufacturers can make it easier to obtain the technical information needed for permitting, but the responsibility still comes down to matching the correct documentation to the exact installed product. At Transform Charleston, we work with trusted manufacturers including Marvin, Andersen and Simonton and help homeowners navigate product selection, installation requirements and project documentation so their exterior improvements are built for Lowcountry conditions and prepared for inspection.
Whether you are replacing a few windows, updating exterior doors or planning a larger whole-home renovation, our team can help identify options that fit the design of your home while also addressing the performance requirements associated with coastal South Carolina.
If you are considering replacement windows or doors for a Charleston-area home, contact Transform Charleston to discuss impact-rated options and determine which Marvin, Andersen, Simonton or other available products may be appropriate for your property and local jurisdiction.
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