TPO & Modified Bitumen Roofing for Additions, Porches & Low-Slope Buildings
Downtown San Jose's denser mixed-use blocks and older home additions often carry low-slope or flat roof sections — a properly drained, correctly installed system holds up well through Bay Area winters.
Where Flat Roofing Shows Up in San Jose
Flat and low-slope roofing isn't just a commercial product — it shows up on plenty of residential additions, porches, and outbuildings too, especially on the older, denser lots common near downtown San Jose. The most common issue we see isn't the material failing outright, it's poor original drainage design letting water pond during a heavy winter storm system and eventually find a seam.
- TPO membrane — reflective, Title 24 cool-roof friendly, and cost-effective for most flat sections.
- Modified bitumen — a durable, multi-layer option for roofs with more foot traffic or rooftop equipment.
- Drainage correction — re-sloping or adding drains where standing water has been a recurring problem.
What's Included
- Free inspection, including a drainage assessment.
- Written estimate covering membrane, flashing, and any drainage correction.
- Full installation with manufacturer warranty documentation.
- Cleanup and final walkthrough.
Explore by Service
Commercial Roofing
Low-slope systems for local businesses and property managers.
Learn more about Commercial RoofingGutter Installation
Properly sized drainage that pairs with a flat roof system.
Learn more about Gutter InstallationFlat Roofing Questions
What's the difference between TPO and modified bitumen?
TPO is a single-ply membrane, generally more affordable and a strong cool-roof performer with a reflective white surface. Modified bitumen is a multi-layer asphalt-based system, often a better fit for roofs with more foot traffic or equipment. We'll recommend the right one for your specific structure.
Do flat roofs actually work in San Jose's rainy winters?
Yes, when installed and sloped correctly for drainage. A properly installed low-slope roof sheds water toward drains just as effectively as a pitched roof — most flat roof leaks trace back to a drainage or seam issue, not the material itself being unsuited to rain.
How long does a TPO or modified bitumen roof last?
TPO typically runs 20-30 years, modified bitumen similar, depending on membrane thickness and installation quality.
Do you repair flat roofs, or only replace them?
Both. Many flat roof issues — a failed seam, a clogged drain, isolated membrane damage — are a repair, not a full replacement. We'll tell you honestly which one your roof needs.
Dealing With a Flat Roof Issue?
Free estimate, honest repair-vs-replace guidance.