Equipment
Split Base Flashing
- You See
- A crack where the membrane turns up the curb.
- What It Means
- Heat and vibration work the corner. New base flashing is set at the required height.
San Tan Valley, AZ
San Tan Valley Commercial Roof Repair
San Tan Valley commercial roof repair for leaks at rooftop units: curb base flashing, cover panels, and pitch pans repaired with the unit left on its curb.
San Tan Valley Commercial Roof Repair At HVAC Curbs
Shopping centers, offices, and service buildings in San Tan Valley carry rooftop units on nearly every suite. When a ceiling stain sits below a unit, the leak almost always comes from the curb: base flashing that split or pulled away, loose counterflashing, or open joints in the cover.
Most of these get fixed with the unit left in place. It only comes off when the curb has rotted or sits too low for new flashing. Since July 1, 2026, the town has shared some building services with Pinal County, so we confirm the permit desk first.
- Base flashing rebuilt at full height
- Counterflashing refastened and sealed
- Cover panel joints resealed
- Pitch pans at gas lines refilled
- Unit stays running on its curb
Curb Problems Behind San Tan Valley Leaks
Rooftop units move, vibrate, and get serviced often. These are the spots that open up.
Sun
Loose Counterflashing
- You See
- The metal cap at the top of the curb flashing pulled away.
- What It Means
- Rain runs behind the flashing. The counterflashing is refastened and sealed.
Age
Cracked Pitch Pans At Gas Lines
- You See
- Gaps in the fill around gas and electrical lines.
- What It Means
- Shrunk fill lets water run down the pipe. Pans are cleaned and refilled.
Foot Traffic
Punctures At Service Panels
- You See
- Small cuts in the membrane by unit access doors.
- What It Means
- Technicians kneel there with tools. Patches and a walkway pad protect the spot.
Monsoon Rain
Open Cover Panel Joints
- You See
- Water inside the unit cabinet or dripping from the curb.
- What It Means
- Wind-driven rain gets through panel seams. Joints are resealed with compatible sealant.
What Repairs Protect In San Tan Valley Buildings
Fixing curb leaks in place protects the tenants below and the equipment above.
Unit Running
Pulling a unit to fix a leak means downtime and a crane.
The RepairRe-flashing in place keeps cooling running for the tenant.
Ceiling Below The Unit
Water drips into ceiling grids and ductwork under the unit.
The RepairSealing the curb stops the drip at the grille and protects the ductwork.
Insulation At The Curb
Moisture wicks into the insulation around the curb base.
The RepairWet board near the curb is replaced before the new flashing goes on.
Technician Damage
Repeat service visits puncture the same patch of membrane.
The RepairA walkway pad from the hatch to the unit spreads the load.
Roof Repair Options For San Tan Valley Buildings
Curb leaks usually involve one or both of these services.
Commercial Roof Leak Repair
Confirms whether the stain under the unit comes from the curb or a nearby seam.
Commercial Roof Leak Repair details
Flat Roof Repair
Base flashing, pitch pans, and membrane patches around units on low-slope roofs.
Flat Roof Repair detailsDrip Under A Rooftop Unit?
Call with the suite or room below the unit and how long it has been dripping. Curb leaks are usually fixed with the unit left on its curb.
Fixing A Curb Leak In Place
Four steps, with the unit left on its curb.
Step 1: Inspect Your Roof
We check the curb flashing, counterflashing, cover panels, and nearby pitch pans, and measure curb height to confirm new flashing will reach the required height.
Step 2: Open The Old Flashing
Failed base flashing and old mastic come off down to clean membrane, and any wet insulation at the curb base is cut out.
Step 3: Rebuild At The Curb
New base flashing goes on at full height, counterflashing is refastened and sealed, and cover panel joints are resealed.
Step 4: Test With The Unit Running
The curb gets a water test with the unit running, and the ceiling below is checked for any drip.
Other Areas Near San Tan Valley
Nearby areas and the repair each one sees most.
- Queen Creek
Storm damage photographed before wind repairs.
- Sun Lakes
Clubhouse vent boots and penetrations resealed.
- Gilbert
Logged stopgaps for open businesses.
- Price Corridor
Piping and conduit leaks on plant roofs.
San Tan Valley Roof Repair Questions
Answers on curb leaks, units, and permits.
Can Leaks Around Rooftop HVAC Units Be Fixed Without Removing The Unit?
Usually, yes. Most curb leaks come from base flashing that has split or pulled away, loose counterflashing, or open joints in the unit's sheet-metal cover.
The curb can be re-flashed in place, the cover resealed, and cracked pitch pans around conduit and gas lines replaced. The unit only comes off if the curb has rotted or sits too low for new flashing.
Who Issues Building Permits In San Tan Valley Now?
The Town of San Tan Valley, with some building services run through Pinal County agreements since July 1, 2026. Because the arrangement is new, we confirm which desk handles a given roof repair before larger work starts.
When Does A Unit Have To Come Off Its Curb?
The inspection decides it. Base flashing has to reach a set height above the finished roof surface, and some older or added curbs sit too low for that. In those cases the curb is raised, which means lifting the unit, and that work is planned with your HVAC contractor.
Do HVAC Technicians Damage Roofs?
Not on purpose, yet the area by a unit's access panels takes the most traffic on the roof. Tools, screws, and kneeling wear through membrane over time. Patching those spots and adding a walkway pad from the roof hatch to each unit prevents repeat punctures.
What Does A Curb Leak Look Like From Inside?
A stain or drip at the ceiling grille or diffuser under the unit, water inside the duct, or wet ceiling tiles in a ring around the supply. After heavy rain, look at the grille first, since that is where curb leaks usually show.
Should The Unit Be Running During The Repair?
For most of it, yes. Flashing work happens around the curb while the unit runs. A shutdown is only needed if the cover panels have to come off or work happens near electrical connections, and that is scheduled with your HVAC contractor.
Do Pitch Pans Need Regular Upkeep?
Yes, a look every spring and fall. The fill around gas lines and conduit shrinks and cracks in the heat, and a cracked pan leaks straight down the pipe. Topping off or refilling a pan is a small repair compared with the ceiling it protects.
Fix The Curb, Keep The Unit Running
Request a free estimate or call about a leak under a rooftop unit in San Tan Valley.