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Maintaining a cold storage roof means monitoring something you cannot see. The program is built around indirect evidence.
Track refrigeration energy
Record energy use per unit of stored product monthly and chart the trend.
A steady rise with no operational explanation is the earliest available indication that insulation is wet. It precedes visible symptoms by years and it costs nothing to collect.
Inspect from inside
This is not optional on this building type.
Walk the underside on a schedule looking for frost at fasteners, frost or ice along deck seams, staining, ice accumulation at any penetration, and condensation dripping onto product.
Photograph the same locations each time so change is visible.
Control penetrations absolutely
Adopt a rule that no new roof penetration is made without design review.
Where a penetration is unavoidable, it must be sealed to the vapor retarder as well as to the water barrier, and the detail must be documented.
Keep a register of every penetration and what it serves. At reroof, anything serving nothing is closed permanently rather than reflashed.
Rooftop equipment discipline
Check refrigeration piping insulation continuity where it passes through and along the roof.
Check condensate terminations quarterly and redirect any discharging onto the membrane.
Inspect equipment supports for point loading and for damage to the surface beneath.
Surface inspection, twice a year
The usual commercial scope: seams, terminations, flashings, drains, ponding, edge metal, walkway pads.
Map ponding carefully. A wet area on this building type is more serious than on an ordinary roof.
Infrared survey, and read it differently
Commission a moisture survey every three to five years.
Interpretation differs here. On an ordinary roof, thermal anomalies indicate wet insulation. On a cold storage roof the temperature differential is large and the signature is different, so use an operator experienced with refrigerated buildings and confirm findings with cores.
Cores, carefully
Core sampling on a cold storage roof breaches the vapor retarder by definition.
It is still the right thing to do when evidence points to a wet assembly, but the patch has to restore the vapor retarder as well as the membrane, and it must be done by someone who understands that.
Keep the whole record together
Energy data, interior inspection photographs, surface inspection reports, moisture survey results and the penetration register.
Read together, these tell you the condition of an assembly you cannot open. Read separately, none of them do.
