Quick comparison
| Factor | TPO | Metal | Mod Bit |
|---|---|---|---|
| Cost/sq ft | $5-$10 | $8-$16 | $4-$8 |
| Lifespan | 20-30 years | 40-60 years | 15-20 years |
| Energy efficiency | Excellent (reflective) | Good (with coating) | Fair (dark surface) |
| Title 24 | Compliant | With coating | With granulated cap |
| Best for | Low-slope, budget | Long-term, any slope | Flat, budget |
TPO (Thermoplastic Polyolefin)
TPO is the most popular commercial roofing membrane in California, and for good reason:
- Energy efficient — white reflective surface meets Title 24 cool roof requirements
- Cost-effective — lower installed cost than metal
- Heat-welded seams — stronger than adhesive-based systems
- Chemical resistant — handles HVAC discharge, grease, and industrial chemicals
- Ideal for Central Valley — handles UV exposure and thermal cycling well
Best for: warehouses, retail, offices, restaurants — any low-slope commercial building where cost and energy efficiency matter.
Metal roofing (standing seam)
Metal is the premium choice for commercial buildings that need maximum longevity:
- 40-60 year lifespan — outlasts every other commercial system
- Fire resistant — Class A fire rating
- Works on any slope — low-slope to steep
- Recyclable — 100% recyclable at end of life
- Low maintenance — no recoating needed
Best for: buildings with a long ownership horizon, agricultural structures, manufacturing facilities, and buildings where fire resistance is critical.
Modified bitumen
Mod bit is the tried-and-true flat roof workhorse:
- Lowest upfront cost — budget-friendly for large flat roofs
- Proven technology — evolved from built-up roofing (BUR), decades of track record
- Easy to repair — patches and maintenance are straightforward
- Multi-layer protection — 2-3 layers provide redundant waterproofing
Best for: budget-conscious flat roof replacements, buildings being sold or renovated within 15-20 years.
Central Valley commercial considerations
- Heat: TPO and coated metal are best for energy savings in 100°F+ summers
- HVAC loads: reflective roofing can reduce cooling costs 15-30% for commercial buildings
- Title 24: all new commercial roofs must meet California cool roof requirements
- Solar ready: consider solar panel compatibility when choosing your system
DeHart Roofing commercial services
We install all three systems and help you choose the right one for your building, budget, and goals. Our commercial roofing team serves businesses across the Central Valley. Get a free commercial roof assessment.
Frequently asked questions
TPO is the most popular choice for Central Valley commercial buildings due to its excellent heat reflectivity, Title 24 compliance, and cost-effectiveness. For long-term value, standing seam metal is the premium choice.
A typical commercial reroof takes 1-3 weeks depending on building size, system type, and weather. TPO is fastest to install; metal takes longer due to custom fabrication.
In the Central Valley, TPO is generally better because its white reflective surface reduces cooling costs and meets Title 24. EPDM (rubber) is black and absorbs heat, making it less energy efficient in hot climates.
Yes. All three systems support solar panels, but mounting methods differ. TPO and mod bit roofs use ballasted or mechanically attached mounts. Metal roofs use clamp-on systems that do not penetrate the roof.