Single-Ply Roofing
San Jose & the South Bay
Bright white reflective TPO membrane — heat-welded seams, Title 24 compliant, 20-30 year manufacturer warranties. The dominant commercial flat-roof system in the Bay Area, installed by a Keith Roofing crew that's been doing single-ply since the 1990s.
Single-Ply Roofing
Done Right Since 1952
Single-ply roofing is the dominant commercial flat-roof system in the Bay Area today — and TPO (thermoplastic polyolefin), the bright white reflective membrane shown in the photo, is the system we install on the vast majority of commercial single-ply projects we take on. Keith Roofing has been installing commercial flat-roof systems since the 1960s and single-ply since it became commercially viable in the 1990s. We're certified installers for Carlisle SynTec Sure-Weld, GAF EverGuard, and Firestone UltraPly TPO systems — the three major manufacturers whose warranty programs cover most Bay Area commercial work.
Single-ply has largely replaced older multi-ply systems (BUR and modified bitumen) for new commercial flat-roof installation. The reasons are real: substantially better energy performance — the white membrane reflects 70%+ of solar radiation vs. 10-15% for traditional dark surfaces, which directly reduces summer cooling loads on Bay Area commercial buildings. Heat-welded seams form continuous waterproof joints — no glue to fail over time. Longer warranties — 20-30 year manufacturer terms are standard, with extended NDL warranties available on premium specs. Better chemical resistance and simpler long-term maintenance round out the picture. For most new commercial flat-roof projects in the Bay Area, single-ply is the default recommendation.
Our single-ply work covers the full range: new commercial flat-roof installation on new construction; full replacement of aging BUR or modified bitumen systems; overlay installation on existing sound roofs (where appropriate); commercial repair and seam work on existing single-ply systems; and silicone coating systems as life-extension alternatives to full single-ply replacement on aging commercial roofs. We work with property managers, building owners, tenants, and facilities teams across the South Bay.
Understanding Single-Ply Roofing
Why Single-Ply Dominates Commercial Flat-Roof Work
Modern single-ply roofing combines the puncture resistance and flexibility of rubber membranes with the heat-weldable seams and reflective surface of thermoplastic chemistry. The result, developed through the 1990s and maturing through the 2000s, now has 25+ years of real-world performance data behind it. Formulations from the major manufacturers (Carlisle, GAF, Firestone, Johns Manville) deliver 20-30 year warranted service life with performance that generally exceeds expectations.
The reflective white surface is a significant benefit in the Bay Area climate. California Title 24 energy code requires cool-roof compliance on most commercial re-roofs (minimum 3-year aged solar reflectance of 0.55 for low-slope roofs). White TPO meets this handily, typically with aged reflectance of 0.65-0.70. The energy benefit is real and measurable: commercial buildings with bright white single-ply roofs experience measurably lower cooling loads, particularly during Bay Area summer afternoons.
Installation Methods: Mechanically-Fastened vs. Fully-Adhered
Single-ply systems install in two primary methods. Mechanically-fastened systems use plates and screws through the membrane into the deck, covered by the next membrane seam. Fastening pattern varies by wind-uplift zone (interior, perimeter, corner) and is dictated by the manufacturer's spec for the building's exposure category. Mechanically-fastened is cost-effective, faster to install, and the typical choice for most commercial buildings with steel or wood decks.
Fully-adhered systems use adhesive to bond the membrane directly to the insulation or cover board substrate. More expensive and slower to install, but eliminates visible fastener points and delivers better wind-uplift performance for high-exposure buildings. Also preferred for buildings sensitive to noise — wind flapping on mechanically-fastened membrane can be audible from indoors, which doesn't happen with fully-adhered work.
The Role of Insulation and Cover Board
Below the single-ply membrane, proper insulation matters significantly. California Title 24 prescribes minimum R-value (typically R-25 for the Bay Area's Climate Zone 3-4), delivered through polyisocyanurate (polyiso) insulation in 1-4 inch thickness depending on existing building insulation. For retrofits, we install above-deck insulation to meet current code requirements even when the original building was insulated to a lower spec.
Cover board — high-density polyiso, gypsum, or fiberboard layered above the insulation — provides puncture resistance and proper substrate for the membrane. Skipping cover board is a common shortcut that reduces long-term membrane performance, particularly on roofs with foot traffic or rooftop equipment. We don't skip it.
When Single-Ply Roofing
Is the Right Answer
New Commercial Flat-Roof Construction
For most new construction commercial work in the Bay Area, single-ply is the default choice. Energy performance, warranty length, and installation economics all favor it.
Aging BUR or Modified Bitumen
Many Bay Area commercial buildings still have BUR or mod-bit installed in the 1980s-2000s. When those systems reach end of service life, single-ply is typically the right replacement — better energy performance, longer warranties, lower maintenance.
Title 24 Cool-Roof Compliance Required
California's Title 24 energy code requires reflective surfaces on most commercial low-slope re-roofs. White single-ply meets this directly — no compliance gymnastics required.
High Solar Exposure on the Roof
Bay Area summer sun is hard on dark roofs. The reflective white surface measurably reduces summer cooling loads — typical buildings see 15-25% lower roof-attributable cooling demand vs. dark-surface alternatives.
Tenant-Sensitive Operations
Single-ply install is faster and quieter than multi-ply alternatives. For occupied buildings where tenant disruption matters, the shorter install timeline matters.
Solar-Coordinated Replacement
Most Bay Area commercial buildings with rooftop solar already use single-ply underneath. We coordinate solar panel detach-and-reset with the original solar installer or a partner — full single-ply replacement under existing solar arrays is a common project for us.
Single-Ply
Brands We Install
Carlisle Sure-Weld TPO
Industry-leading single-ply product line. 45-mil, 60-mil, 80-mil membrane options. Fleece-backed available for certain substrates. 20-30 year warranty options. Strong Bay Area distribution.
GAF EverGuard TPO
GAF's single-ply line with warranties up to 30 years from certified installers. Good Bay Area service support. Various thickness and accessory options.
Firestone UltraPly TPO
Firestone's TPO single-ply system. Strong long-term track record. Extended Red Shield warranties available on premium specs.
Johns Manville TPO
Johns Manville's single-ply with solid Bay Area distribution and competitive warranty terms. Common on retrofit specifications.
Polyiso Insulation
Above-deck polyisocyanurate insulation to current Title 24 R-value (typically R-25+ for the Bay Area). Tapered systems available for proper drainage on flat decks.
Cover Board & Accessories
High-density polyiso or gypsum cover board for puncture resistance. Walk pads, drain assemblies, parapet flashing kits, and HVAC curb flashings rounded out per project.
How We Handle
Your Single-Ply Project
Site Visit & Assessment
On-site evaluation of existing roof, deck condition, insulation, drainage patterns, HVAC, solar, and access constraints. Photo documentation of pre-project conditions.
System Spec & Written Quote
Line-itemed quote covering tear-off, deck repair allowance, insulation, membrane, flashings, and disposal. Manufacturer warranty options spelled out. Multiple system specs where appropriate.
Permit & Title 24 Documentation
Permit pull through the relevant jurisdiction (San Jose, Santa Clara County, or the specific city). Title 24 cool-roof compliance documentation prepared and submitted with the permit application.
Tear-Off, Insulation & Membrane Install
Phased tear-off where the building is occupied. Insulation and cover board to spec. Membrane installed mechanically-fastened or fully-adhered per the spec. Seams heat-welded, then probed for continuity.
Closeout Documentation
Post-install photos, scope description, material specifications, manufacturer warranty registration, and our workmanship warranty — all delivered as a packaged record suitable for reserves or insurance files.
Why Property Managers Choose Us
for Single-Ply Roofing
30+ Years Installing Single-Ply
Keith Roofing has been installing single-ply since it became commercially viable. That depth of experience shows up in proper seam-welding technique, realistic performance expectations, and pattern recognition for what fails on Bay Area buildings.
Certified Across All Major Brands
Certified installer status across Carlisle Sure-Weld, GAF EverGuard, and Firestone UltraPly. Multi-brand certification means we can spec the right system for the building rather than the brand we're locked into.
Property Manager Operational Fit
Written scope, photo documentation, tenant communication, manufacturer warranty registration, clean billing. Standard practice. Property management firms keep us on their lists because we handle the operational side correctly.
Solar-Coordinated Work
The Bay Area has very high commercial-solar density. We coordinate panel detach-and-reset with the original solar installer or a partner — single-ply replacement under existing rooftop solar is a routine project for us, not an exception.
Recent Single-Ply
Commercial Projects
Projects Featuring
Our Single-Ply Roofing Service
Real Keith Roofing projects featuring commercial single-ply work. Click any case study for the full story.
Crown Blvd Commercial
14,000 sq ft commercial single-ply install with tapered insulation, Title 24 compliance, and a 20-year manufacturer warranty.
View Case Study →
San Jose Apartment Re-Roof
Multi-unit apartment full replacement — shingle on pitched wings, single-ply on flat carports, full gutter replacement.
View Case Study →San Jose Commercial Maintenance
Ongoing commercial flat-roof maintenance with single-ply install and solar panel coordination.
View Case Study →