Robotic field welds
Constant heat and speed across every field sheet, logged by day and area.
Thermoplastic Polyolefin
TPO, welded and tested seam by seam
Robotic hot-air welded thermoplastic membrane in 45, 60 and 80 mil — high reflectance, energy-code compliant insulation and curb flashing details that survive rooftop HVAC service traffic.
- Robotic welding
- CRRC rated
- 45 / 60 / 80 mil
- Solar Reflectance Index
- SRI 100+Solar Reflectance Index
- Seam peel strength
- > specSeam peel strength
- CT energy code target
- R-30CT energy code target
- NDL warranty available
- 30 yrNDL warranty available
Welding
The seam is the roof
TPO seams are fused, not glued. A robotic welder holds a constant temperature, speed and pressure down the full length of the sheet, producing a homogeneous weld that is stronger than the membrane beside it.
We probe every seam daily and cut destructive test coupons to confirm peel strength exceeds the manufacturer's published minimum. Details too tight for the robot — curbs, drains, corners — are hand-welded and probed twice.
Weld records go in the close-out package with the warranty registration, which is what the manufacturer inspector asks for on an NDL job.
Hand-welded details
Curbs, pipe boots, drain sumps and corners welded and probed individually.
Destructive testing
Daily coupons pulled to verify peel strength beyond published minimums.
Documented close-out
Weld logs, as-built assembly and warranty certificate issued together.
Engineering
Membrane gauge comparison
| Engineering spec | |||
|---|---|---|---|
| Nominal thickness | 1.14 mm | 1.52 mm | 2.03 mm |
| Coating over scrim | ~15 mil above scrim | ~22 mil above scrim | ~32 mil above scrim |
| Solar Reflectance Index (white) | 104 initial / ~79 aged | 108 initial / ~83 aged | 110 initial / ~85 aged |
| Wind uplift rating (typical) | FM 1-60 typical | FM 1-90 achievable | FM 1-90 / 1-120 with enhancement |
| Static puncture resistance | ≈ 200 lbf (ASTM D5602) | ≈ 300 lbf (ASTM D5602) | ≈ 400 lbf (ASTM D5602) |
| Chemical exposure | Limited — no grease or solvent exposure | Good — PVC formulation for grease exhaust | Best — full grease, oil and process exhaust |
| NDL warranty available | 15 year | 20–25 year | 30 year NDL |
| Expected service life | 15–20 years | 20–25 years | 25–30+ years |
Where 60 mil belongs
The commercial standard and our default specification. The extra coating above the scrim is what buys the second decade of service life.
Energy
Reflectivity and Connecticut code
SRI above 100
White TPO reflects the majority of solar gain, cutting membrane surface temperature and easing summer cooling load on rooftop units.
CRRC-rated values
We specify membranes with published Cool Roof Rating Council initial and three-year aged reflectance and emittance values.
Energy code insulation
Polyiso layers staggered and offset to hit the Connecticut energy code R-value with no thermal bridging at the board joints.
Wind uplift design
Fastening pattern calculated per ASCE 7 zones, with enhanced perimeter and corner density.
Details
HVAC curbs, the usual failure point
Most TPO roofs that leak are not leaking in the field. They leak where a service tech set a unit back down on a crushed curb wrap, or where a condensate line was drilled through the membrane after the roof was signed off.
We flash curbs with prefabricated corners, run the membrane to the top of the curb under the unit's counterflashing, and set walkway pad routes from the hatch to every serviceable unit so techs never walk the field membrane.
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