Commercial Roofing in San Antonio: Understanding Roofing Code Compliance
Posted on Wednesday, September 27th, 2023 at 6:01 pm
If you’re a building owner or property manager interested in commercial roofing in San Antonio, then you should understand general roofing codes to ensure compliance. Although roof inspectors are trained in building codes, it’s beneficial for commercial property owners to be aware of standard municipal, state, and international roofing laws.
Understanding roofing codes not only promotes structure and occupant safety, but it also allows property managers to hold their roofing contractors accountable for proper building regulations. From roofing materials to storm drainage requirements, here is an overview of roofing codes for commercial roofing in San Antonio.
A Complete Guide to Code Compliance for Commercial Roofing in San Antonio
Roofing codes are based on various factors, including roofing system types, services, materials, physical condition, and building size. There are also municipal, state, and international construction and property improvement laws.
It’s important to note that this guide is a general overview of roofing code compliance for commercial roofing in San Antonio. Always refer to a third-party roof inspector and a qualified roofing company for further guidance on roofing codes and regulations.
Municipal Permit Requirements for Roofing Contractors: Roof Replacement, Windows, Siding, and Doors
Did you know that San Antonio requires roofing contractors to obtain a permit for specific roofing services? Roofing contractors that recover or replace your roof, windows, siding, and doors require a registered permit in the city of San Antonio before starting any work.
For non-structural building improvements, like re-roofs (no changes in roof pitches), San Antonio roofers must submit a site plan and permit. If you find that your roofing company doesn’t have the proper permits for your project, San Antonio municipal law states that the work must be stopped until they’re acquired.
Before hiring commercial roofing contractors, confirm they are registered in San Antonio to prevent the risk of risk costly citations for breaching city ordinances and codes. This ensures that your building is meeting legal standards, prevents liability issues, and confirms the service quality is following the law.
Depending on the service provided, a roof inspector may be required to visit your property once it’s complete. Even if it’s minor structural improvements, we always recommend investing in roof inspections as an added safety measure, especially for commercial properties. Depending on your property insurance provider, a roof inspection may be required regardless.
Wind-Resistance Codes
Texas is known for its strong weather conditions. Different areas of the state experience hurricanes, hail, tornadoes, and strong storms, which can cause severe roof damage. For these reasons, roofing systems must be designed and installed to be weather-resistant for optimal strength, lifespan, and storm protection.
Texas state codes for weather-resistant commercial roofing include:
- Roofs must be constructed to withstand strong wind conditions equal to 1 ¼ times the pressures (applied to outward surface only)
- Roofs or roof sections with slopes greater than 30 degrees must be designed to withstand 1 ¼ times the wind pressures (applied to the inward slope only)
- Nails, clips, and other similar attaching devices must be corrosion-resistant or galvanized
| Height Zone (Feet) | Wind Pressure (Lb. Per Sq. Ft.) |
| Less than 30 | 35 |
| 50 to 99 | 45 |
| 100 to 499 | 55 |
| 500 to 1,199 | 70 |
| 1,200 and above | 90 |
Credit: Texas Administrative Code, Figure: 28 TAC §5.4007(a)(2)(A)(i)
Wind pressure requirements for commercial roofing in San Antonio are calculated by height zone to determine the proper strength. Depending on your building size and common weather conditions, weather-resistant strength codes will vary.
Water Drainage Codes
In addition to wind resistance, San Antonio also requires storm drainage codes for commercial roofing. Water damage can cause serious building damage, such as mold, accelerated deterioration, and cave-ins. With severe storms, the amount of water and related roof damage can increase significantly without proper drainage systems.
San Antonio commercial roofing codes for storm drainage include:
- Roof edges less than three feet of any property line must have gutters and downspouts to direct roof water away from adjacent property
- Drip edges are now required on all roofs per the city code to provide additional waterproofing protection
- Roof flashing must be sound, tight, and have no defects to prevent dampness and deterioration from water
- Roof drains, gutters, and downspouts must be adequately maintained and obstruction-free
If you find standing water, mold, or clogged gutters on your roof, these are signs to get your water drainage system repaired immediately. Roof maintenance and repairs should be done routinely and timely to prevent water damage from turning into more costly and dangerous issues.
International Fire Codes
Fire prevention is not only a life-saving measure, but it is legally required for commercial buildings. In addition to fire sprinkler systems, extinguishers, designated exists, and emergency vehicle access lanes, roofs must also be fire safety-compliant.
Texas fire codes for commercial roofing include:
- Roof installations cannot be any more than 55ft above the lowest level of required fire department vehicle access
- Roof heights must be measured from the greatest distance between one of the following:
- The lowest required fire vehicle access road surface next to the building to the eave of the highest-pitched roof
- The intersection of the highest roof to the exterior wall
- The top of the highest parapet
As a commercial property manager or owner, you never want to put occupants’ safety at risk due to a lack of fire compliance. If your roof is over 20 years old, we always recommend getting it inspected by professional roofers or building inspectors. They’ll assess your roof’s condition and ensure it doesn’t interfere with your fire safety and emergency response systems.
Roofing Material Installation Codes
When it comes to commercial roof installation, specific standards are set for each roofing material type. The Municode Library states that all roofing materials must pass the U.L. Standard 997 or a comparable test certified by the Commissioner. San Antonio also requires all roofing materials to have some form of wind resistance.
However, with various roof materials, like metal and asphalt shingles, it’s important to know the building code differences in each. Below is a brief breakdown of roofing installation codes by material type.
Single-Ply Roof Material Codes
Single-ply roofing systems (SPS) are strong flexible sheets that are typically made of synthetic polymer with strict quality control requirements. SPS roofing is made of three materials: polyvinyl chloride (PVC), thermoplastic polyolefin (TPO), and ethylene propylene diene monomer (EPDM). Since there are multiple SPS roofing materials, building code requirements may differ.
The Building Code of the Texas IHB states their regulations for SPS roof installation include:
- Low-slope single-ply roofing with metal edge securement must be installed within wind load regulations
- Thermoset single-ply roofs must have a minimum 2% slope for water drainage
Due to their consistent physical composition, SPS is a popular material option for commercial roofing in San Antonio since they’re pre-fabricated to be code compliant. If your building is flat or low-sloped, SPS roofing is a practical option due to its flexible physicality.
Metal Roof Material Codes
Metal roofing materials are often made of steel, aluminum zinc, tin, seam-standing metal, and copper. They also have various adhesion techniques, including exposed fasteners, concealed fasteners, and concealed adhesives. Due to the differences in material composition and applications, metal roofing codes may vary.
According to the Building Code of the Texas IHB, regulations for metal roof installation include:
- Shingles must not be installed on roof slopes below 25% slope
- Roof deck shingles must be applied to a solid or closely fitted deck unless it’s designed to be applied to spaced sheathing
- Shingle roof coverings must be naturally corrosion resistant
One of the main benefits of metal roofs is that they’re one of the most long-lasting materials with an average 50-year lifespan. Once your metal roof is installed with routine maintenance, you can have access to simpler code compliance due to its strong durability.
Tile Roofing Material Codes
There are two types of tile roofing materials: concrete and clay. Commercial buildings commonly use tile in their roofing systems since they’re weather and fire-resistant. If you want a new tile roof installed in your commercial building, it’s imperative to ensure it’s compliant since they’re designed to last long-term– at least 50 years!
The Municode Library states that San Antonio regulations for tile roof installation include:
- Tile roofing must be installed with no less than one layer of 30lb asphalt felt and securely fastened by nailing with tin caps
- All tiles must be thoroughly watered with a hose before applying
- Each tile must be laid full length in portland cement mortar
- The first three horizontal shingle courses must be nailed in
- Additional nailing may be required to prevent the tile from slipping in certain conditions
- Mortar cannot be not less than one part cement and three parts sand, and not more than 25% lime by volume
- All nails for roof flashing and tiles must be copper
Whether you choose clay or concrete tile roofing, ensuring proper preparation and installation is crucial to prevent them from slipping, becoming unnecessarily damaged, and failing inspection.
Asphalt Shingle Roofing Material Codes
There are three types of asphalt shingles: standard three-tab, laminated, and premium. Laminated and premium shingles are heavier than standard three tabs, so installation requirements may differ.
According to the Municode Library, San Antonio regulations for shingle roof installation include:
- Roll roofing cannot be applied over shingle roofs
- Shingle layers must be spot-mopped and applied by concealed nails
- Nails must have a minimum head lap of three inches, an end lap of six inches, and must be properly cemented
- Nail spacing on shingle roofs cannot be less than four inches on centers
- Thick-butt asphalt shingles must be nailed in the thickest areas
If your asphalt shingle roof is close to 30 years old, we always recommend getting it maintained and inspected by quality roofers with experience in this material.
Built-up Roofing (BUR) Material Codes
Built-up roof (BUR) systems are also known as asphalt flat roofing. They’re installed either through cold-applied adhesives or coal tar. Since these are typically flat or lower-sloped roofing systems, it’s critical to ensure it has strong water drainage.
The Municode Library states that San Antonio regulations for BUR roof installation include:
- Cant strips must be installed on roof angles and vertical surfaces for coverings
- BUR coverings must be at least six inches above the cant strip to a reglet in the parapet and covered with metal flashing caulked into the reglet.
- BUR roof felt layers must be applied vertically, properly lapped, and cemented to the parapet
If your BUR roof is over 15 years old, you should get it inspected and maintained as suggested by your commercial roofer to prevent damages, safety risks, and failing building codes.
Wood Roofing Material Codes
Although using wood as a roofing material is less common nowadays to minimize fire risks, there are fire-retardant-treated wood options available. Some businesses, like restaurants, have outdoor covered patios and hotels with penthouses or rooftop bars, which commonly use fire-resistant wood for their roofing materials.
According to the Municode Library, San Antonio regulations for wood roofing installation include:
- Wood roof decks with prepared shingles should be solidly sheathed, well-seasoned, and dry
- Sheathing boards must be at least one-inch nominal dimension boards and not over six inches wide
- Plywood sheathing must be at least ⅝ of an inch thick
- Outdoor covered areas must have fire retardant-treated wood as per IBC Section 2303.2 or protected with a fire-resistance-rated material approved by the city
- All resinous wood roof deck areas must be covered with sheathing paper or unsaturated felt
If you choose to install or upgrade your wood roofing system, always ensure that the materials you’re using are protected with fire-resistant treatment.
Keep Your San Antonio Commercial Roof Compliant with Kidd Roofing
Meeting municipal, state, and international roofing codes is complex. Regulations differ based on roofing systems, the materials used, building size, and more. While it’s essential for commercial property owners to comprehend basic roofing regulations, it can be challenging to navigate on your own.
At Kidd Roofing, we can help guide you through any commercial roofing service, including roof inspections and insurance company claims. We’re proud to have been installing and repairing commercial roofing systems in San Antonio since 1982. Our contractors are fully licensed, insured, and registered to ensure complete credentials for any size project.
Keep your San Antonio property compliant with qualified commercial roofing services.
Contact us for a free quote today!
