We get this question every week: 'Should I do TPO or modbit on my flat roof?' The honest answer depends on your roof's quirks, but here's what we're actually charging in 2025 and what we'd choose ourselves.
Installed cost (1,800–2,200 sq ft flat roof)
Across our last 28 flat-roof bids in Bernalillo and Sandoval counties:
- 60-mil mechanically attached TPO: $11,400–$17,800 ($6.20–$8.90 / sq ft installed)
- SBS-modified bitumen with reflective cap: $9,800–$15,200 ($5.40–$7.60 / sq ft installed)
- EPDM (less common in ABQ): $9,200–$14,400 ($5.00–$7.20 / sq ft installed)
Where TPO wins
TPO's white reflective surface dropped one Nob Hill client's summer cooling bill 19%. It qualifies for the PNM cool-roof rebate. Manufacturer warranties run 20–25 years.
It's also the easiest to spot-repair — heat-weld a patch and you're done.
Where modbit wins
Modbit handles roof traffic better. If you've got HVAC techs walking your roof twice a year, modbit absorbs that abuse where TPO can develop puncture wear over time.
It also handles complex penetrations and parapets more forgivingly — the torch-applied cap molds to detail work that TPO would need flashing kits for.
What we'd put on our own house
Simple roof, few penetrations, want lower bills? TPO. Complex roof, lots of HVAC, historic look matters? Modbit with reflective cap. Either way, the underlayment and drainage detail work matters more than the membrane choice itself.