Commercial roofing refers to the installation, repair, and replacement of roofing systems on non-residential buildings like office buildings, warehouses, retail centers, schools, churches, and multi-family properties. These roofs are typically flat or low-slope, and they’re designed for long-term waterproofing, energy efficiency, and durability.

The best commercial roofing material depends on your building type, roof slope, drainage, budget, and long-term performance goals. At Washington Weather Shield, we recommend the best system for your property based on what will perform best in Western Washington weather.

Top commercial roofing materials include:

• TPO (Thermoplastic Polyolefin): Durable, energy-efficient, great for flat roofs
• PVC (Polyvinyl Chloride): Excellent waterproofing, strong long-term performance
• EPDM (Ethylene Propylene Diene Monomer): Cost-effective rubber membrane option
• Roof Coatings: Can extend roof life when conditions allow

Metal Roofing: Best for sloped commercial roofs and longevity

Choosing the right commercial roofing contractor directly impacts long-term performance, safety, and doing the job right the first time. At Washington Weather Shield, we recommend looking for a contractor with:

• Proven commercial roofing experience (especially with flat and low-slope systems)
• A company that specializes in commercial roofing, not primarily residential work
• Manufacturer accreditations and certifications from top roofing brands
• Ongoing training hours with leading roofing manufacturers to stay current on proper installation methods
• Strong references, clear communication, and detailed proposals with scope and warranty details

Washington Weather Shield meets these standards through our commercial-focused expertise, manufacturer-backed training and certifications, and our commitment to delivering professional, long-lasting roofing systems built for Western Washington weather.

Budgeting for commercial roofing in Seattle starts with understanding your roof size, roof type, and whether you need repairs, restoration, or a full replacement. 

Key factors that affect commercial roofing cost include:

• Roof size (square footage) and number of roof levels
• Roof system type (TPO, PVC, EPDM, metal, or coatings)
• Existing roof condition and whether tear-off is needed
• Insulation upgrades and energy-efficiency goals
• Drainage, penetrations, and roof detail complexity (curbs, skylights, parapets, etc.)
• Access and safety requirements (staging, crane use, occupied buildings)
• Warranty level and desired roof lifespan

For the best budgeting results, Washington Weather Shield recommends planning early, comparing multiple options (repair vs restoration vs replacement), and choosing a system that delivers the best long-term value—not just the lowest upfront cost.

Installing commercial metal roofing requires careful planning, proper safety measures, and manufacturer-approved installation methods to ensure long-term performance. Metal roofing is typically installed on sloped commercial roofs and is designed to provide strong weather resistance.

In general, commercial metal roofing installation includes:

• Inspecting the roof deck and confirming proper slope and drainage
• Removing old roofing materials (if needed) and preparing the surface
  Installing underlayment, waterproofing, and required flashing details
• Laying out and fastening metal panels correctly (alignment is critical)
• Sealing seams, penetrations, edges, and transitions to prevent leaks
• Installing trim, ridge caps, and gutters/downspouts as required
• Completing a final inspection for watertightness and quality control

Because metal roofing performance depends heavily on correct detailing and fastening, Washington Weather Shield recommends having commercial metal roofing installed by an experienced commercial roofing contractor to protect your building and warranty coverage.

The best way to protect a commercial roofing system is through routine inspections, proactive maintenance, and fast leak response, especially in Western Washington where heavy rain can expose small issues quickly. 

Top ways to protect your commercial roof include:

• Schedule regular roof inspections (especially before and after winter)
• Keep drains, scuppers, and gutters clear to prevent ponding water
  Fix small leaks early before they turn into major damage
• Limit rooftop foot traffic and use walk pads where needed
• Maintain flashing and penetrations (vents, curbs, skylights, HVAC)
• Remove debris and standing water to reduce wear and deterioration
• Document repairs and maintenance to support warranty requirements

To find a reliable commercial roofing contractor, look for a company that specializes in commercial (not residential) roofing, has proven experience with flat and low-slope systems, and can provide clear documentation and references. At Washington Weather Shield, we recommend checking for:

• Commercial roofing experience (TPO, PVC, coatings, metal, repairs, replacements)
• Proper licensing, insurance, and strong safety practices
• Manufacturer certifications and training with top roofing brands
• Detailed proposals with clear scope, timeline, and warranty options
• Strong reviews, referrals, and local project examples

If you’re searching in the Seattle area, Washington Weather Shield provides commercial roofing services across the Puget Sound and can help you evaluate the best solution for your building.