Commercial flat roofs are a staple of modern architecture, offering practical solutions for businesses in San Diego and beyond. Unlike steeply pitched residential roofs, flat roofs provide additional usable space, accommodate HVAC systems, and align with the sleek aesthetic of commercial buildings. However, their design also makes them prone to specific challenges, such as water pooling, UV damage, and wear from foot traffic. For property owners and facility managers here in San Diego, understanding the process of repairing commercial flat roofs—along with the applicable industry standards, permitting requirements, and common roofing systems—is critical to maintaining a durable, leak-free structure. This article, crafted from the perspective of a San Diego roofing company, provides an in-depth look at the repair process, ensuring compliance and longevity for your commercial property.
Before diving into repair techniques, it’s essential to recognize the most prevalent types of commercial flat roofing systems in San Diego. The region’s mild climate, occasional heavy rains, and intense sunlight influence the choice of materials and maintenance needs. Here are the primary systems you’ll encounter:
Built-Up Roofing (BUR)
Often referred to as “tar and gravel” roofs, BUR systems consist of multiple layers of asphalt and reinforcing fabrics, topped with a gravel or mineral surface. These roofs are durable and resistant to foot traffic, making them ideal for San Diego’s commercial buildings with rooftop equipment. However, their multi-layer construction can complicate leak detection and repairs.
Modified Bitumen (Mod-Bit)
A hybrid of BUR, modified bitumen roofs use asphalt membranes reinforced with polyester or fiberglass, often applied with a torch-down or adhesive method. These systems offer flexibility and UV resistance, suited to San Diego’s sunny conditions. Repairs typically involve patching or resealing seams.
Single-Ply Membranes (TPO, PVC, EPDM) Commercial Roof Types
TPO (Thermoplastic Olefin)
A popular choice in San Diego due to its energy efficiency and reflective white surface, TPO reduces cooling costs in the region’s warm climate. Repairs often address seam failures or punctures.
PVC (Polyvinyl Chloride)
Similar to TPO, PVC offers excellent durability and chemical resistance, commonly used in restaurants or industrial buildings. Welded seams are a key repair focus.
EPDM (Ethylene Propylene Diene Monomer)
Known as “rubber roofing,” EPDM is a cost-effective, weather-resistant option. Repairs typically involve patching with liquid rubber or tape.
Spray Polyurethane Foam (SPF)
SPF roofing involves spraying a foam layer topped with a protective coating. Its seamless application is ideal for San Diego’s irregular roof shapes, but repairs require recoating or patching damaged areas.
Each system has unique strengths and vulnerabilities, and a professional San Diego roofing company will assess the roof type before recommending repairs. Factors like age, exposure to coastal salt air, and prior maintenance history also play a role.
The Commercial Roof Repair Process: Step-by-Step Guide
Repairing a commercial flat roof is a systematic process that demands precision, safety, and adherence to industry standards. Always hire a licensed and insured local roofing company with good reviews and commercial roof experience. Not only is the work dangerous, but it can also cost tens of thousands of dollars to fix some mistakes during repair or installations. Here is a basic breakdown of the typical steps a commercial roofing company may follow:
Step 1. Initial Roof Inspection and Assessment
The process begins with a thorough inspection. Roofers climb onto the roof to evaluate its condition, looking for signs of damage such as cracks, blisters, seam separation, pooling water, or punctures. If possible, we also use a drone to inspect and assist us as needed. In San Diego, special attention is paid to UV degradation and debris accumulation from nearby trees or coastal winds. Infrared scanning or moisture detection tools may be used to identify hidden leaks—a common issue given flat roofs’ minimal slope.
Step 2. Documentation and Local Permitting
Before repairs begin, documentation is key. For significant repairs or alterations in San Diego, a building permit may be required under the California Building Code (CBC), Title 24, enforced locally by the City of San Diego Development Services Department. Per the 2022 CBC Section 1505, roofing repairs exceeding 25% of the roof area within a 12-month period may trigger a full re-roofing permit and compliance with current energy efficiency standards, such as cool roof requirements (Title 24, Part 6). A reputable San Diego roofing company will verify permit needs and submit plans if necessary, ensuring compliance with local codes.
Step 3. Roof Surface Preparation
Once approved, the roof surface is cleaned and prepped. Debris, dirt, and loose gravel are removed using brooms, blowers, or power washers. For BUR or SPF roofs, damaged sections may need to be cut away. This step ensures proper adhesion of repair materials and prevents future failures.
Step 4. Roof Repair Execution
The repair method depends on the roofing system and damage extent:
- BUR: Leaks are patched with hot asphalt and new felt layers, followed by a gravel topcoat to match existing areas.
- Modified Bitumen: Torch-applied or self-adhesive patches seal seams or holes, with granules added for UV protection.
- Single-Ply (TPO/PVC): Heat-welded patches or adhesive tapes repair tears, with seam reinforcement as needed.
- EPDM: Liquid rubber coatings or EPDM tape are applied over cleaned, primed areas.
- SPF: Damaged foam is removed, and new foam is sprayed, followed by a fresh elastomeric coating.
In San Diego, contractors often apply reflective coatings post-repair to enhance energy efficiency, aligning with Title 24 cool roof mandates.
Step 5. Waterproofing and Testing
After repairs, seams and penetrations (e.g., HVAC mounts, vents) are sealed with caulk or flashing. A flood test or electronic leak detection may be conducted to confirm it is water-tight. This is needed to protect your business roof during San Diego’s rainy season (typically November to March).
Step 6. Final Inspection and Maintenance Plan
The roofing company performs a final walkthrough, ensuring all repairs meet manufacturer specifications and local codes. Clients receive a maintenance plan, recommending quarterly inspections and debris removal to prolong roof life in San Diego’s variable climate.
Industry Regulations for Commercial Roofs and Specific Codes & Permits in San Diego
Repairing and replacing commercial flat roofs in San Diego involves navigating a web of regulations designed to ensure safety, durability, and environmental compliance.
Key standards include:
- California Building Code (CBC), Title 24: Based on the International Building Code (IBC), the CBC governs roofing construction and repairs. Section 1511 mandates that repairs maintain the roof’s original fire-resistance rating, while Section 1507 outlines material standards for flat roofs (e.g., ASTM compliance for membranes).
- Title 24, Part 6 (Energy Efficiency): San Diego commercial buildings must meet cool roof requirements for repairs exceeding 50% of the roof area or 2,000 square feet, whichever is less. This often means installing materials with a minimum solar reflectance index (SRI).
- OSHA Safety Standards: Roofers must follow Occupational Safety and Health Administration guidelines (29 CFR 1926), including fall protection for work above 6 feet—a critical concern on flat roofs with parapets or equipment.
- City of San Diego Municipal Code: Chapter 14, Article 2 regulates construction permits and stormwater management, requiring proper drainage solutions to prevent pooling, a frequent issue on flat roofs.
Non-compliance can result in fines, project delays, or legal liability, making it essential to hire a licensed San Diego roofing contractor familiar with these rules.
Common Commercial Roof Repair Challenges Roofers May See San Diego
For Alma Roofing and other local roofing companies, San Diego’s climate and urban environment present unique challenges for flat roof repairs:
- UV Exposure: The city’s abundant sunshine accelerates material breakdown, especially on BUR and single-ply roofs. Regular coatings or reflective upgrades can mitigate this.
- Coastal Corrosion: Proximity to the Pacific Ocean exposes roofs to salt-laden air, corroding metal flashing or fasteners. Stainless steel or corrosion-resistant materials are recommended.
- Rain and Drainage: Though rainfall is modest, sudden storms can overwhelm poorly maintained drains, leading to leaks. Repairs often include unclogging or upgrading drainage systems.
- Foot Traffic: Rooftop HVAC units and solar panels—common in San Diego—invite technician traffic, risking punctures. Protective walkways can prevent damage.
Addressing these issues proactively ensures repairs last, saving businesses from costly replacements. A reputable commercial roofing company will also provide detailed estimates, code-compliant solutions, and post-repair support.
For expert assistance with commercial roofs in San Diego, contact us here at Alma Roofing today to schedule a free inspection and keep your commercial flat roof in top condition.
